The CICA Windows Explosion!/The CICA Windows Explosion! - Disc 1.iso/desktop/ozw108d.zip/wozgis.doc

Text File | 1995-04-11 | 850KB | 11,292 lines

                                OzGIS

                                V10.8


                            For WINDOWS3.1

                             (April 1995)

















                         The Clever Company.

                         QMDD Box 6108,
                         Queanbeyan,
                         Australia 2620.

                         FAX [phone]


                                                                       2
               PREFACE

OzGIS is a software system for displaying geographically referenced data as
coloured maps on graphics display devices. The maps portray the data
values associated with geographic zones by uniform colours, site data by
different sized symbols, and line data by different line types.
The system can be used to analyze socio-economic and demographic
data produced by censuses and surveys and to support management decisions
associated with for example marketing, sales, site and personnel location,
and advertising. Other spatial data such as environmental data can be displayed.

The software was originally developed as part of a research project at the
Division of computing Research of the Commonwealth Scientific and Research
Organisation (CSIRO) in Canberra for a mapping product called COLOURMAP.

Software development started in 1979 with the purchase of hardware that had
been developed for the DIDS mapping system in the White House in Washington DC.
This hardware consisted of a PDP11 mini-computer and a DeAnza display system.
The display featured a 12bit frame buffer, 4096 value primary look-up table and
cascaded 256 value colour table. This enabled maps of up to 4000 zones (e.g.
USA Counties) to be displayed and manipulated very rapidly, and is the best
hardware so far produced.

The environment changed over several years, with moves to larger PDP11 systems
and to VAX and CDC machines. Several display systems were used, Tektronix,
Jupiter and RAMTEK, and maps were generated on plotters and film recorders. The
system was also available on CSIRONET, an Australia-wide computer network with
Control Data and FACOM host computers. The 1981 ABS Census data could be
accessed via the SIR/CENSYS system on the Cyber 845. A system was developed to
handle the Census district boundaries digitised by the Division of National
Mapping, to enable windowing, line simplification and aggregation for production
of geographic map data files. The SAS system was available on the FACOM 180 for
statistical analysis and display of map data.

The first year of development was supported by Techway, and APASCO supported
the development of techniques for retail applications. APASCO used the system
and hardware for several years as part of their consulting activities to churn
out thousands of maps.

 The Division of computing research was split into the CSIRONET computing bureau
and the new Division of Information Technology in 1985. Later, CSIRONET was
given to private industry. The mapping project was abandoned.

The software was resurrected in late 1990 and ported to the IBM PC to produce
the current system.

 The purpose of the Guide is to introduce the facilities of OzGIS. The Guide is
intended to complement the messages and assistance given during the operation of
OzGIS.

 The user should understand the techniques of statistical data analysis and
computer mapping, and also have an elementary understanding of colour
representations.


                                                                       3


The Clever Company is a Canberra based software company offering consulting and
contract programming services in the areas of:

. C and FORTRAN programming
. Spatial databases
. Scientific applications
. Graphics
. UNIX workstation, minicomputer and PC environments

The Clever Company was formerly Geismar Holdings Pty Ltd.


                                                                       4
                    1. OzGIS INTRODUCTION
                       ==================



This chapter gives an overview of the programs in the OzGIS system, the concepts
behind the design of the system, and something about the software.




  1. 1 Programs
       --------


The OzGIS system is available for DOS and WINDOWS3.1

The DOS system consists of several modules:

OzEnter  - for entry of data files into the system.
OzData   - preparation of data for mapping
OzZone   - formation of polygons / lines structure from line segments
OzGIS    - interactive display and analysis
OzCensus - Display and analysis of Census type data (subset of OzGIS)
OzGISco  - maths coprocessor version of OzGIS
OzMap    - output of saved displays on plotters and printers and to files
OzTerr   - definition of territories from zones
OzCatch  - site catchment analysis
OzProj   - map projections
OzSpat   - spatial operations

The WINDOWS version allows more RAM to be used, so most of the programs can be
combined (as was the original version).

WOzGIS    - most of the system. A variation allows for simple Census mapping
WOzMap    - output of saved displays on plotters and printers and to files

Note that you can only run one program at a time under WINDOWS.

Start mapping with the Simple Census Mapping program, which is a subset
of the OzGIS program.

  1. 2 Concepts
       --------

 OzGIS aims to accept basic data files and to provide most of the facilities
required for the analysis and display of attribute data as maps. The
analyst has to be able to rapidly use the facilities, so OzGIS provides an
interactive user interface. The user interacts via menus and is aided by on-line
assistance.

 Visual inspection of choropleth maps is the intuitive way to interpret the
spatial features of data. An analyst needs to be able to rapidly display and
manipulate maps to aid his understanding. OzGIS was designed to enable maps to
be changed within seconds so the analyst does not lose his train of thought.

 OzGIS enables the analyst not just to display a map, but to generate the map

                                                                       5
that best shows the features of the attribute data. A hardcopy map can be
generated as the final operation as a record or for dissemination.

Easy to use systems are either trivial systems, or have a small number of
options. The enormous number of options within OzGIS means that it takes
some time to understand everything. However, maps can be produced quite simply
by using only a small number of options and by using the system defaults.


 OzGIS can be considered as one system of a facility for analysis and display
of Census type data. The various components are:

 - Database systems for manipulation and retrieval of attribute data
 - Systems for generation of map boundary data
 - Statistical analysis systems with graphic display and reporting facilities
 - Mapping systems with analysis and hardcopy facilities.

Hence you may use:
a CAD package for digitising geographic data
a database system for storing attribute data
a spreadsheet for manipulating numeric data
a statistics program for analysis
etc

 It is expected that an analyst would have access to a PC close to his
office. The PC/workstation may be connected via a computer network to
provide access to large host machines. The host machines would contain the
database systems from which map data could be extracted, and other systems for
analysis and hard-copy generation.


  1. 3 Environment
       -----------

 OzGIS requires advanced raster display systems for rapid display of maps.
Unfortunately PC display systems are extremely limited in capability. In
particular only a maximum of 256 colours are available (on 512K super VGA
boards). OzGIS is able to generate maps on most graphic devices by using polygon
fill to colour map zones. This faciity also allows for hardcopy generation of
maps previewed on raster displays.  PC display systems do not have hardware
polygon fill, so map display is slow.

 OzGIS is based on the GKS graphics standard. The standard provides device
independence, and the basic graphic capabilities of lines, text and fill. OzGIS
does contain its own set of GKS-type routines which can be used to interface to
display devices with hardware fill capabilities or to other device independent
packages. The INTERACTOR graphics package is used for the DOS version,
and the SCIPLOT package for hardcopy map production. The WINDOWS API is used
for the WINDOWS3.1 version.

 OzGIS is a large FORTRAN program. It will run on computer systems with a
FORTRAN 77 compiler and about a mega-byte of memory. The system is well
structured, so by using overlays and reducing capabilities (array sizes) the
software can be implemented in smaller memory machines. Hence OzGIS is
reasonably portable.  The PC version is heavily overlayed to fit it into the
artificial 640K limit imposed by the DOS operating system. Later additions to
OzGIS are also being coded in 'C' and C++.


                                                                       6

The WINDOWS3.1 version enables extended memory to be used, although system
limits still prevent the hardcopy (SCIPLOT) part being incorporated into the
main program. A 386 with at least 4Meg of RAM and a mouse is required.

Generally the speed of the system is dependent on hardware:

Processor 286 -> 386 -> 486
Disk speed
Floating point processor
Extra memory for RAM disk

INTERACTOR is a graphics package produced by:

Interactive Software Services,
25 St Michael's Close,
Penkridge,
Stafford. ST19 5AD.
U.K.

We have found INTERACTOR very good, and the support is excellent.

SCIPLOT is a plotting package produced by:

MicroGlyph Systems,
PO Box 474,
Lexington, MA 02173,
U S A

                                                                       7
                    2. INSTALLATION
                       ============



This chapter describes how to set up the OzGIS system and how to make the
best use of your hardware.

The READ.ME file supplied on the first floppy disk is a shorter version of this
chapter and may be an easier way to get started.





  2. 1 Installation
       ------------


The software is supplied on floppy disks with most files compressed by
the PKZIP program.

The files must all be first copied to the hard disk drive that you are going to
use into a directory that must be \OZGIS.


The installation procedure is as follows:

1. set up the \OZGIS directory

CD \
MKDIR OZGIS

2. copy all files from floppy disk to the \OZGIS directory

CD \OZGIS
COPY a:*.* (for each disk)

3. Run the installation procedure

INSTALL


  2. 2 Documentation
       -------------

The manual is usually supplied on disk as OZWIN.DOC

The WOTSNEW.DOC file contains details of changes to the system.

  2. 3 Directories
       -----------

The installation process sets up two directories:

\ozgis contains OzGIS system files
\ozdemo contains example map files

                                                                       8

You should also set up at least one directory for your own use e.g. \mapping
Your own directories must be on the same disk drive as \ozgis


  2. 4 Environment
       -----------

OzGIS should run on any WINDOWS3.1 system with at least 4Meg of RAM, a 386 or
486 processor, and a mouse.

Refer to the "Trouble Shooting" chapter if you have memory problems.

  2. 5 Display Drivers
       ---------------

Standard VGA screens are adequate for simple maps, but it is recommended that
you purchase a super VGA video card and monitor to obtain the highest screen
resolution and the highest number of colours possible. 1MByte super VGA boards
that provide 1024X768 pixels and 256 colours are recommended.

You have to run SETUP in the c:\windows directory to install the driver for a
super VGA board. See the WINDOWS manual.

OzGIS is very demanding and it is suspected that some manufacturer's drivers
may be inadequate. If you have problems try a more standard VGA driver.

  2. 6 Installion in WINDOWS
       ---------------------

Installation requires setting up a program group and then defining
program items in it. This is described fully in the WINDOWS documentation.

The installation process will copy a program group file for OzGIS for the C:
drive, and will also attemp to copy to the D: drive. You will have to modify the
group for other drives, or if your \WINDOWS directory is not on the C: drive.

To set up a program group, select "New" from the "Files" menu in the Program
Manager and give the program group file as "OZGIS.GRP"

This will pick up the files from \WINDOWS where it was placed by the
installation procedure. You may find that the icons are not enabled.


For example:

Suppose the directories are on disk drive D: as D:\OZGIS, D:\OZDEMO and
D:\MAPPING

Then the groups should look like:

Description:     Demonstration
Command line:    d:\ozgis\ozdemo.exe
Work Directory:  d:\ozdemo

Description:     Demo OzGIS
Command line:    d:\ozgis\wozgis.exe  12   (dont leave off the 12!!)
Work Directory:  d:\ozdemo

                                                                       9

Description:     Demo Simple Census Mapping
Command line:    d:\ozgis\wozgis.exe  15
Work Directory:  d:\ozdemo

Description:     Demo OzMap
Command line:    d:\ozgis\wozmap.exe
Work Directory:  d:\ozdemo

Description:     Demo Vector
Command line:    d:\ozgis\vector.exe
Work Directory:  d:\ozdemo

And a similar set for your own directory:

Description:     Mapping
Command line:    d:\ozgis\wozgis.exe 12
Work Directory:  d:\mapping

Description:     Census-type mapping
Command line:    d:\ozgis\wozgis.exe 15
Work Directory:  d:\mapping

Description:     Hardcopy maps
Command line:    d:\ozgis\wozmap.exe
Work Directory:  d:\mapping

Description:     Metafile output
Command line:    d:\ozgis\vector.exe
Work Directory:  d:\mapping


Whenever you start a new project you will probably set up a new directory and
then define some program items to reference that directory.

Some of the versions of WINDOWS do not allow you to give a working directory. In
this case the working directory will be where the program is executed from i.e.
/OZGIS. You will then find it easiest to do all your mapping in \OZGIS. First of
all move the \OZDEMO demonstration files to \OZGIS i.e.
      cd \ozgis
      copy  \ozdemo\*.*
      del   \ozdemo\*.*
      rmdir \ozdemo


  2. 7 OzGIS initialisation file
       -------------------------


The file \OZGIS\OZGIS.INI is the initialisation file for the system.

The file should NOT have to be modified initially.

The file should be well commented, and modifications should be fairly obvious.
Ensure that you dont alter the columns used i.e. the file is not free format!

The first three lines should define you video board (although the system
currently gets the information from the WINDOWS screen driver).

                                                                      10


e.g. for the VGA board

       640         Number of pixels across VGA screen
       480         Number of lines on screen
        16         Number of colours

The initial user interface settings for trace and help levels are here. You can
modify them later if you like.

You can also control the automatic redisplay of maps after you select a new
option.

An important part of the file is the entries that define the fonts that are
used. There is more information about these in the section on the formats of
device files.

The first font in the list is usually used (set to Arial initially).

You can view the fonts on your system by choosing the Fonts icon in the Control
Panel window.

If you find that no text is displayed on maps you probably do not have the
usual fonts installed so will have to change to one that you have.

Fonts have to be variable size so TrueType fonts should be used.

There has been some problems setting correct sizes so dont change fonts unless
there is good reason to do so.


  2. 8 Demonstration
       -------------


You should start by looking at the OzGIS demonstration which consists of a
series of saved maps.

You can run the demonstration from the item in the program group you just set
up.


  2. 9 First Example Map
       -----------------


The first example is a choropleth map of Australia, which is an example of a
very common type of map to display attributedata like Census data, sales data,
or government statistics.

Within WINDOWS run the "Demo OzGIS" program item that you just set up.

Choose Map from the toolbar, and then DISPLAY ZONES FOR AN ATTRIBUTE FILE
from the pulldown menu.

give the attribute file name as OZ


                                                                      11
give the geographic file name as OZ

You will have a default map with legend and distribution diagram. The legend
has the numbers of zones in each class on the left and the class value ranges
to the right of the coloured boxes.



  2.10 Second Example Map
       ------------------


The next example is the display of digitised map data for Hawaii. These types
of maps show polygon (here islands), line (roads, rivers etc) or points data
(e.g. towns).

Select "Top menu" from the Files menu.

Choose the Map pulldown menu again, and then DISPLAY GEOGRAPHIC FILES.

Choose the menu option DISPLAY POLYGONS FROM A GEOGRAPHIC FILE

Give the file name as "HAWDLGWB".

Accept the default polygon number and give the legend text as "Hawaii".

Accept the default (No) for drawing polygon boundaries.

The islands of Hawaii will be drawn.

Choose the option OVERLAY LINE SEGMENTS FROM A GEOGRAPHIC FILE

Give the file name "HAWDLGST"

Accept the default line number and give the legend text as "Rivers".

This example uses two files originally in DLG-3 optional format, off the USGS
CD-ROM.  This is a simplified example; usually feature codes in these files are
used to subset the data e.g. to draw rivers and streams in different colours.


Finally -

Choose "Quit" from the Files menu.

  2.11 Hardcopy configuration
       ----------------------

Configuration for production of hard-copy maps via OzMap is described in the
appendix.

                                                                      12
                    3. DATA ENTRY
                       ==========



This chapter shows how to import your data into the OzGIS system.







  3. 1 Introduction
       ------------


Most data are entered into OzGIS as external data files. Examples are Census
data and Census digitised boundaries. These files come from Census Bureaux,
Mapping agencies, data supply companies or your own data-base systems.
Some data can be prepared or modified with word processors or spreadsheets.

Several data fornmats are supported. If your format is not supported
you have to convert it into one of the supported formats or the OzGIS standard
format for the type of file.

The data entry options are initiated by choosing IMPORT DATA FILES from the
File menu.

The main menu enables selection of the type of file:

IMPORT GEOGRAPHIC FILES
IMPORT ATTRIBUTE FILES
IMPORT A NAMES FILE
IMPORT A COMBINE FILE
IMPORT A DEVICE FILE
IMPORT A MARKER FILE

Choosing a menu item may generate another menu e.g. for GEOGRAPHIC FILES

IMPORT A STANDARD FORMAT GEOGRAPHIC FILE
IMPORT NEW FORMAT SAS GEOGRAPHIC FILE
IMPORT OLD FORMAT SAS GEOGRAPHIC FILE
IMPORT A DLG-3 OPTIONAL FORMAT GEOGRAPHIC FILE
IMPORT A GINA FORMAT GEOGRAPHIC FILE
IMPORT A TIGER FORMAT GEOGRAPHIC FILE
IMPORT A DIME FORMAT GEOGRAPHIC FILE
IMPORT A DXF FORMAT GEOGRAPHIC FILE
    .
    .
    .
    .

where DLG-3, TIGER, DXF etc are different data formats.


In all cases, data entry requires giving the name of your data file and

                                                                      13
supplying the name to be used for the internal file.


Data files usually have names that finish with the extension DAT.
e.g. LONDON.DAT, A:SALES.DAT.

The one time a full file name can be given within OzGIS is when reading a data
file, as it is sometimes inconvenient to rename files (but typing L for a list
of files will only list those with extension .DAT). For example you may have
TIGER files from the US Census bureau on CD-ROM. Then you could read the files
directly by giving the complete file name e.g. E:/18/003/TGR18003.F42

Often data files will need further processing before used for mapping e.g.
attribute data may need manipulating by arithmetic expressions or geographic
line segments may need thinning and forming into polygons.

Future versions of the OzGIS system may have incompatible internal file formats
so always keep important data files.

The system comes with many of the system files already entered e.g. device
files. The data files are also provided.

  3. 2 Example of data entry
       ---------------------

You will often have a file of attribute data (such as population Census
data) and a file of digitised boundary data for mapping (e.g. TIGER):

We will look at data for Australia. There are two data files:

OZ-G.DAT are the digitised boundary data, (Australian Statistical Divisions)
OZ-A.DAT are the attribute data

Execute the OzGIS program for the demo directory.

Choose IMPORT DATA FILES from the File pulldown menu.

A menu will appear like:

1 TUTORIALS & SYSTEM INFORMATION
2 IMPORT GEOGRAPHIC FILES
3 IMPORT ATTRIBUTE FILES
4 IMPORT A NAMES FILE
5 IMPORT A COMBINE FILE
6 IMPORT A DEVICE FILE
7 IMPORT A MARKER FILE

You select the options by moving up and down with the arrows and pressing Enter
or by typing the number.

The system trace is usually turned on so messages will appear on the screen
during processing.



First enter the digitised boundary data:
---------------------------------------


                                                                      14

Select the option to IMPORT GEOGRAPHIC FILES

The next menu appears:

1 IMPORT A STANDARD FORMAT GEOGRAPHIC FILE
2 IMPORT NEW FORMAT SAS GEOGRAPHIC FILE
3 IMPORT OLD FORMAT SAS GEOGRAPHIC FILE
4 IMPORT A DLG-3 OPTIONAL FORMAT GEOGRAPHIC FILE
5 IMPORT A GINA FORMAT GEOGRAPHIC FILE
6 IMPORT A TIGER FORMAT GEOGRAPHIC FILE
7 IMPORT A DIME FORMAT GEOGRAPHIC FILE
8 IMPORT A DXF FORMAT GEOGRAPHIC FILE
9 IMPORT AUSLIG SEGMENTS FORMAT CENSUS BOUNDARY FILE

This enables geographic data to be read in in a variety of "standard" formats.

The test data is in the OzGIS standard format so choose
IMPORT A STANDARD FORMAT GEOGRAPHIC FILE

A  data input window now appears for you to specify a file name. You type in
what you want and then type enter:

give the input data file as OZ-G
give the output geographic file as OZ

The data file will be processed, and a standard geographic file created.

The trace message at the bottom of the screen describes what is going on.



Now enter the attribute data:
-----------------------------

select the option to IMPORT ATTRIBUTE FILES

A new menu appears:

1 IMPORT A STANDARD FORMAT ATTRIBUTE FILE
2 IMPORT A SPREADSHEET WK1 FORMAT FILE
3 IMPORT A DATABASE (SIMPLE) FORMAT ATTRIBUTE FILE
4 IMPORT A LAMM FORMAT ATTRIBUTE FILE
5 IMPORT USA CENSUS STF 1A FILES FOR TRACT/BNA
6 IMPORT USA CENSUS STF 1A FILES FOR BLOCK GROUPS
7 IMPORT ATLAS DATA FILES

The data are in standard form so:

Select IMPORT A STANDARD FORMAT ATTRIBUTE FILE

give the input data file as OZ-A
give the output attribute file as OZ

3. The data files are now entered so -

If you use the Files Manager to look in the directory \ozdemo you will find
that there are two new files there:

                                                                      15


OZ.ATT is the attribute file and
OZ.GEO is the geographic file.

You (almost) never give a full file name within OzGIS - the system appends
a file extension to the name according to the file type.


  3. 3 Demonstration Files
       -------------------

The OzGIS system is supplied with a complete set of sample external
data files so that the user can become familiar with the system.  These
files can be inspected to clarify the file formats.

The files are usually in the directory \OZDEMO and have names DEM*.*

  3. 4 Example geographic and attribute data
       -------------------------------------

Generally there will be two data files for each map; a file that describes the
map boundaries and another for attribute data. The example files are:

1. Far East Asia

Attribute file - FEA-A
Geographic file- FEA-G


2. Lowe electorate (Sydney)

Attribute files- LOWE-A1 and LOWE-A2
Geographic files- LOWE-G (zones), LOWE-S1, LOWE-S2 (sites)

These files are already entered (supplied with the system).

3. Australia

Attribute file - OZ-A
Geographic file- OZ-G

These files have already been input in the demonstration chapter.

4. Washington DC Census Tract/BNA and TIGER lines

These have been entered off CD-ROM files and preprocessed ready for display.

attribute file WASHTRACT
Geographic zones file WASHTRACT
Geographic lines file WASHROADS
Geographic lines file WASHRAIL

5. Africa in Atlas format

Geographic data files AFRICA.DAT

6. Hawaii in DLG-3 optional format

                                                                      16

These came off a USGS CD-ROM

HAWDLGWB.DAT Water boundaries (islands)
HAWDLGAB.DAT administration boundaries
HAWDLGST.DAT streams
HAWDLGRD.DAT roads

7. DXF example files from VIC Roads. These have extensions *.DXF

8. London Cholera

Files are supplied for the classic mapping example where the mapping of the
houses where people died during the 1854 outbreak of Cholera onto a street map
of inner London, and then mapping the water supply, showed clustering about one
pump. The data files are in IDRISI format.
STREET.* London streets (lines)
DEATH.*  Where fatalities occurred (points)
PUMP.*   Locations of water outlets

9. ACT / Canberra

Test data are provided for Canberra.

CANBP1.DAT and CANBP2.DAT are shopping centre locations
ACTSHOP.DAT is sample attribute data for shopping centres

L81SEG.DAT are 1981 Census boundaries for the ACT. This file is Crown Copyright
of AUSLIG, Australia's national mapping agency. It is supplied with the
permission of the General Manager, Australian Surveying and Land Information
Group, Dept Arts and Admin. Services, Canberra, ACT.

L81ATTR.DAT is sample attribute data for the above (mangled Census dervived
data). L81.ATT is the enetered data.

ACTSUBURB.DAT is a points file of names of Canberra suburbs (LGAs).
ACTSUBUR.GEO is the enetered geographic file.

ACTMT.DAT is point data for ACT mountains.

Two files for site catchment examples are:
CATCH.CAT example site catchments and
CANBL81.GEO a geographic file for Canberra city.

10. D.C.W.

The Digital Chart of the World is an extensive vector database supplied
on 4 CD-ROMs at mimimal cost.

The test data are from the low resolution browse database. The files are:

DCWLAND - World polygons (PO lines data param file modifed to give lines
131, 132 feature code 99 - these close asia at the edges)

DCWPOTXT - polititical names

DCWPPPNT - pop places locations


                                                                      17
DCWPPTXT - pop places names

DCWDNLN - drainage lines


Feature codes:

DCWLAND - none

DCWPOTXT - 1=land place names, 2=ocean place names
           6=mountains, 8=islands, 10=deserts

DCWPPPNT - none

DCWPPTXT - none

DCWDNLN - 1 = rivers, 2=inland shorelines



  3. 5 Example device files
       --------------------

The characteristics of devices and the appearance of maps are given by display
files. Data files are provided for all the device files supplied with the
system. There are two sets for 16 and 256 colour video boards, and also sets
for hatching and colour simulation on plotters etc.

Files are already entered on the system and are described in a later chapter.

  3. 6 Marker data files
       -----------------

These have already been entered, and are supplied with the system. They are
circle, diamond, hbar, nabla, plus, square, triangle, vbar. (You can of course
have your own markers).


  3. 7 Colour names data (no longer used)
       ----------------------------------

This option has been removed as DOS limits were being exceeded.

A colour names file X11-BGR.DAT is supplied and is useful for colour definition.


                                                                      18
                    4. BASIC CHOROPLETH MAPPING EXAMPLE
                       ================================



This chapter gives an introduction to the map display options.





  4. 1 Simple Census-type Mapping
       --------------------------

The Simple Census Mapping Icon can be clicked for simple choropleth mapping.

This provides two or three menus and about twenty menu options while the full
mapping menu tree has about a hundred menus and a thousand menu options.

This option is suitable for simple mapping of Census type data and is
recommended for use while learning to use the system.

When you want to use more advanced mapping use the full OzGIS version.


  4. 2 Example Choropleth Map
       ----------------------

The most common application is the display of data such as Census data as
coloured polygons. Here the processes necessary to display such data are
described.

Census data enables you to display maps that show where people live who
are of different nationalities, ages, income groups etc. These maps are
used for applications such as retail marketing to find where potential
customers are located or for government planning to decide where to build
facilities like schools.

You will probably have a file of attribute data (such as population Census
data) and a file of digitised boundary data for mapping (e.g. TIGER):

We will look at the data data for Australia. There are two data files:

OZ-G.DAT are the digitised boundary data, (Australian Statistical Divisions)
OZ-A.DAT are the attribute data

An example of entering these data files was given in the last chapter.

Both the attribute file and geographic file are called OZ. Different types of
files can have the same name.


Execute the Simple Census Mapping icon for the OzDemo directory.

Choose the option to "DISPLAY A NEW MAP" from the Mapping pulldown menu

give the attribute file name as OZ.

                                                                      19

When asked for the geographic file name input "L". A list of the available files
will appear. Either double click on OZ.GEO or click QUIT and then give the file
name as OZ (not OZ.GEO!).

The data are now processed, the map is displayed, and the next menu appears.

You now have a default map with legend and distribution diagram. The legend
has the numbers of zones in each class on the left and the class value ranges
to the right of the coloured boxes.

The new menu is:

TUTORIALS & SYSTEM INFORMATION
ADD TEXT TO MAP
DISPLAY THE NEXT SEQUENTIAL ATTRIBUTE
SELECT AN ATTRIBUTE FOR DISPLAY BY NUMBER
CHANGE THE NUMBER OF CLASSES
CHANGE THE QUANTISATION METHOD
DISPLAY ATTRIBUTE STATISTICS
LIST ZONES SELECTED WITH BOX-CURSOR
SAVE DISPLAY FOR HARDCOPY MAP GENERATION WITH OzMap
DISPLAY A NEW MAP


Now investigate some of the options:

Choose the option to DISPLAY THE NEXT SEQUENTIAL ATTRIBUTE


Select the option to SELECT AN ATTRIBUTE FOR DISPLAY BY NUMBER.
Type 0 to get a list.

A list of the attributes available will appear in a window.

Click Quit to return to the question. Type in a number to select an attribute.



Note two special entries in the Files menu that appear after a map is
displayed:

"Draw map" will regenerate the displayed map. Usually this happens
automatically. You can also suppress automatic rewraing from the files menu.

"Top menu" must be used from a lower level to return to the start menu.

Now investigate some of the File pulldown menu options:

Select INTERROGATE FILES. Select GEOGRAPHIC FILES and use the file name OZ
(the one displayed).

Other options enable the user interaction to be controlled; try turning on
partial trace (level 1) which causes a series of messages to appear at the
bottom of the screen telling you what the system is doing, but not as many as
level 2. The initial trace levels for all programs are set in the
\ozgis\ozgis.ini file.


                                                                      20
"Quit" is used to exit from the program. Dont use it yet!

Back at the Mapping menu, select CHANGE THE NUMBER OF CLASSES.

change the number of classes to 10.

Select the option to CHANGE THE QUANTISATION METHOD.

Another menu will appear.

QUANTISATION TUTORIAL
USE EQUAL VALUE INTERVALS
USE QUANTILES
USE SELECTED CLASS INTERVALS
USE SELECTED NUMBER OF ZONES PER CLASS
USE REFINED EQUAL VALUE INTERVALS
USE PSEUDO CONTINUOUS-COLOUR
USE THE MEAN AND STD DEVIATION METHOD
USE THE NESTED MEANS METHOD
USE THE NATURAL BREAKS METHOD
USE SELECTED PERCENTILES
USE SELECTED CLASS RANGE PERCENTILES
USE INTERACTIVE SELECTION OF CLASS INTERVAL,
USE EQUIVALENCE CLASSES
USE CURRENT CLASS RANGES
USE CURRENT NO PER CLASS

These options are very important as they enable the map to show the data in a
way relevant to the purpose of the analysis.

For example, to select deciles:

Choose USE QUANTILES and set the number of classes to 10. The legend
will now describe the 10 colours in the map.


Choose the option to DISPLAY ATTRIBUTE STATISTICS.

Basic statistics will be displayed in a window for the displayed map.

Click "Quit" to remove the window.

Choose the option to LIST ZONES SELECTED WITH BOX-CURSOR.
This will enable the current values for the displayed zones to be listed.

A cursor will appear on the screen which indicates the bottom left position.
Place it using either the arrows (type Enter to select the position) or the
mouse (left button to select). A box cursor then appears to select the other
corner. All zones are listed that have a minimum bounding rectangle (MBR)
that intersects the selected window.


  4. 3 Summary
       -------

You now have seen simple examples of the processes to produce maps.

1. you obtain your data as files in a standard format.

                                                                      21

2. you usually set up a directory on the same disk as \OZGIS and put the data
files there.

3. Use IMPORT DATA FILES from the top menu to read in the data files.

4. Use Simple Census-type Mapping or the Full OzGIS system (INTERACTIVE
ANALYSIS menu item) to display.

But ......... this is very simple

You may want to do some data preparation before mapping.

You may have geographic data as line segments and need to form the polygons.

You may want to display other types of maps or diagrams.

You may want to output prepared maps to a printer, plotter or file.

and so on.


                                                                      22
                    5. INTERACTIVE USER INTERFACE TO OzGIS
                       ===================================



The user controls OzGIS by responding to menus, questions and
commands presented on the PC screen.

This chapter describes these forms of user communication.




  5. 1 OzGIS Menus
       -----------

You choose processing and display options from pulldown menus or from
a pop-up menu that appears in the OzGIS window.

The menu changes depending on what you are doing.

      Menus are presented in the format below.  The MENU HEADER
contains the previous menu item selected, or in the case of a main menu
the system title.

               [MENU HEADER]
               [Previous Menu
               [menu item 1]
               [menu item 2]
                         :
                         :
                         :
               [menu item n]

For example, a menu could be:

Previous Menu
TUTORIALS & SYSTEM INFORMATION
IMPORT DATA FILES
PREPARE DATA FOR DISPLAY
INTERACTIVE DISPLAY AND ANALYSIS OF MAP DATA
BUILD TOPOLOGY FROM LINE SEGMENTS
INTERACTIVELY DEFINE TERRITORIES
MAP PROJECTIONS
SPATIAL OPERATIONS ON GEOGRAPHIC DATA

Menu items are selected either by click on an item or holding the left mouse
button down and moving the cursor to the required selection.

You will find that some there are lots of menus, and it is  difficult at first
to know where you are in the menu "tree". To make it more  confusing the menus
are dynamic e.g. adding something to a map can cause a new  menu item to appear
that allows you to delete that item.

The general approach is: if the current menu does not have the option you want
select from the pulldown menu. You will find that you cannot return to a
previous menu at some "main" menus. This prevents loss of map data at various

                                                                      23
stages; Select "Top menu" from the Files menu.



Main menus appear as pulldown menus.



  5. 2 Question Dialog Boxes
       ---------------------

      Questions are asked by OzGIS when data are required for an
operation.  The user must supply the data by entering appropriate responses
in a dialog box.

      The format of questions consists of the question, a possible range of
values in brackets (if appropriate), a default value in parentheses (if
appropriate) and terminated by a question mark.  The range of values and
default values indicate the form of the expected answer.  An example is:

      -  request to replace an existing file:
         DO YOU WANT TO REPLACE THE FILE [Y,N]?


         The user must respond by clicking on YES or NO.

      The following single character responses provide assistance when
answering some questions:

      "H":  presents a "help" or informative message about the required
            response.

      "E":  returns to the previous menu without further action.


      Errors in responses are trapped and result in help messages being
printed.  The user is asked the question again.

  5. 3 Command Dialog Boxes
       --------------------

      Commands are issued by OzGIS when an operation has to be
performed by the user.  When the operation is completed, control returns to
the appropriate menu.

      The format for commands consists of a directive, a possible range of
values in brackets (if appropriate), a default value in the input field (if
appropriate), terminated by a colon.  Examples are:

      -  to provide the number of classes:
         TYPE NUMBER OF CLASSES [1-6] (4):

         The number of classes must be in the range 1 to 6, and if
         the user simply presses the "Enter" key a default value of 4 will
         be selected.

      -  request for the name of a file:
         FILENAME (TEST):

                                                                      24

         The filename must be entered as a character string, or the
         "Enter" key pressed to accept the default filename "TEST".

      The following single character responses provide assistance when
responding to commands:

      "L":  provides a list of data items that can be selected.

            e.g. for FILENAME, a list of available files will be printed.
            e.g. for ATTRIBUTE DESCRIPTION, the names of attributes on the file
            will be listed.

      "H":  presents a help or informative message about the desired
            operation.


      "E":  returns to the previous menu without further action.

Errors in responses are trapped and cause a help message to be printed and
the command to be repeated.

  5. 4 Graphic interaction
       -------------------

      Graphic interaction in OzGIS involves the use of the mouse to control
the cursors on the monitor. Use the left mouse button to select.

      The user is directed to operate the mouse etc by the appearance of the
cursor on the monitor and by an appropriate command on the screen.  The
extent of the command depends on the current level of user communication
(see "User Interface" option).

There are several types of cursors:

. a pointer to select a position of object
. a box to select a region. The bottom left corner is selected and then the
   other.
. a fixed size box to select text positions
. a cursor for selecting a circle (centre first followed by circle)

  5. 5  Print file
       -----------

Every program generates printout on a file OZGIS.OUT.

This includes:

Reports
Error messages
Debug output

Every time a map is interactively queried the list of map items retrieved is
output to a file QUERY.OUT

The windows version also outputs error messages to a file WINDOWS.OUT

                                                                      25
                    6. OzGIS FILES
                       ===========



This Chapter describes the various files which are processed by
OzGIS.  Some of the files can be entered into OzGIS as data, and
the external formats for these files are given later.  All of the
files have internal formats, which are generated as part of the user
interaction.




  6. 1 File Origins
       ------------


The following kinds of files must be entered into OzGIS:

      -  data files
      -  marker files
      -  device files
      -  presentation files
Data files usually come from Census bureaux, map data suppliers or your
corporate database.

External data files must be entered into OzGIS explicitly.  This
operation permits OzGIS to generate internal representations of the
data for efficient processing and to check the data.


Certain files must be prepared explicitly within OzGIS under user
direction.  These files are:

      -  saved display files
      -  catchment files (OzCatch)
      -  time lapse files  (no longer available)
      -  palette files (no longer available)
      -  hardcopy files  (OzMAP)

Some files can be prepared externally or internally.  These are:

      -  geographic files
      -  name files
      -  combine files
      -  colour names file  (no longer available)

Some files are usually prepared with a word-processor.  These are:

      -  presentation files
      -  parameter files


                                                                      26

  6. 2 File types
       ----------


The file types will become obvious with use of the system.

There are many different types of files used:

(a)  Geographic Map files describe geographic (map) data in terms of
     graphic elements - zones, polygons, line networks, line segments and
     points.  The data can be drawn in geographic regions, or overlayed on
     displayed maps.

     The files are generated by digitising base maps.  This is a
     time-consuming soul-destroying task.  Fortunately digitised map data
     are available for many commonly used maps e.g. states, postcodes,Census
     districts.  Where special zones are required, they can often be
     defined in terms of Census districts and the map boundaries obtained
     by amalgamating the digitised Census boundary data (dropping internal
     lines).  This has the additional advantage that Census data can also
     be extracted for the amalgamated zones and used for comparisons with
     the user's own attribute data.

(b)  Attribute files contain the values of attributes (variates,
     statistics, variables) referenced to zone, line or site names.  Each
     file may contain a number of attributes for a fixed set of names.

     Attribute files are processed to assign a class number to zones
     (colour) or lines (line type) or sites (symbol sizes) in a displayed
     map.

     Attribute data files are usually generated via a standard database or
     modelling system or by a user's own programs.

(c)  Names files contain a list of zones, lines or sites that defines a
     geographic region of interest.  The files may be used to subset
     geographic data.  It may also be used to restrict the set of
     attributes to be quantised for a map, or alternatively the set of
     zones lines or sites to be displayed on a map.

(d)  Combine files - define new items in terms of zones.  A file may define
     new zones in terms of amalgamated base map zones or the influence of
     surrounding zones on a site.

     The file contains a list of names of the new zones or sites defined.
     If just one new name is given it is a renaming, if more than one an
     amalgamation.

     For each new item there is a list of the base map zones it is defined
     by and a list of weights.
     New zones are defined by complete base map zones so the weights have
     value 1.0 e.g. Sales Territories. Site Catchments are used to retrieve
     data from underlying map zones so the weights give the proportions of
     the zones (range 0-1).

(e)  Marker files - define simple shapes as single polygons for display as

                                                                      27
     markers.

     The data are simply the (X,Y) points that are used to draw the
     polygons.  The points are in the range -0.5 to +0.5 so the polygon can
     be easily scaled and displayed centred at a location.

(f)  Saved Display files contain the data to regenerate a complete display.
     These files should be stored by the user upon completion of a display
     for later recall.  Subsequent manipulation of the display is possible
     after recall.

     Saved display files are the common level of storage and retrieval of
     maps.  A user may build up a set of commonly displayed maps with all
     the desired features that can be displayed and modified rapidly.
     Saved display files are also used for presentations.

(g)  Presentation files contain references to a number of Saved Display
     files.  The files are used to present a set of displays quickly,
     usually for demonstration purposes.

(h)  Time Lapse files contain a set of attributes for display as a time
     lapse sequence.  All attributes are quantized in the same way by
     OzGIS and must exist on the same file. e.g. data that has been
     collected regularly, say weekly, can be displayed as a 'movie' to see
     if there are any time-based spatial features.
     The format of the files is internal to OzGIS.  These facilities
     are only available for colour display systems with large numbers of
     colours.
     (no longer available as PC hardware is inadequate)

(i)  Device files - define the graphic devices and their capabilities.
     Each device is a GKS workstation.  Several files may exist for each
     device giving different values for the graphic primitive attributes
     (line type, text, colours, patterns etc.).  In particular, each file
     contains sets of fill colours or patterns for single and bivariate
     maps.


(j)  Palette files contain a set of colours which can be selected for
     display.  The set of colours is displayed as a palette during the
     colour selection process.  Colour palette files can be modified and
     generated by user interaction, but their format is internal to
     OzGIS.
     (no longer available)

(k)  Colour Names files contain a set of colour names and associated blue,
     green and red (B,G,R) values for the display system.  The files enable
     users to specify colours by typing a name (e.g. LIGHT RED) on the
     keyboard.  Colour names files can be entered as external data files or
     can be prepared by entering names and indicating the corresponding
     colours.
     (no longer available)

(l)  Hardcopy files - contain information to enable maps to be reproduced
     off-line on other devices (with the vector program)

(m)  Parameter files - contain data for special operations e.g. entry of
     US Census STF1A files, address matching. These files often come from

                                                                      28
     other systems.

(n)  Text Attribute files contain lines of any text and are used to provide
     additional information about map items e.g. a geographic file defining
     the locations of shopping centres may have a text attribute file that
     gives the names, addresses, total floor area and number of customers per
     month.

(o)  Catchment files - contain definitions of sites, boundaries of
     catchments around sites, and catchment weights.  Catchment files are
     interactively generated with reference to a base map.

(p)  Digitising files - contain data generated while digitising a map


  6. 3 File Names
       ----------

OzGIS distinguishes the various types of files, so you can give the same name
to files of different types e.g. you may have a geographic file called AFRICA
and also a (probably related) attribute file called AFRICA and you may save the
map using these files in a saved display file also called AFRICA.

The system differentiates between files by adding an extension to the given
file name e.g. the AFRICA attribute file would actually be AFRICA.ATT

You generally dont have to worry too much about extensions, but they are:

.ATT  attribute files
.CMB  combine files
.DAT  data files
.DEV  device files
.GEO  geographic files
.HRD  hardcopy files
.MRK  marker files
.PRM  parameter files
.PRS  presentation files
.SAV  saved display files
.SCR  screen dump for saved display files
.TMP  temporary scratch files
.DIG  digitiser files

The system just adds the extension on the end of the file name you give, so you
can put any path on the front e.g. an input attribute file could be given as
D:\TEST\AFRICA which the system translates to D:\TEST\AFRICA.ATT

There is actually two exceptions - because data files are often obtained from
elsewhere and you may want to input them directly off floppy disk or CD-ROM
(where files cannot be renamed) you can give a full file name when entering
external data files. Similarly, parameter files often come from other
systems with naming conventions, so a full file name can be given.
When you ask for a file listing the standard dialog box function includes the
file extensions.

                                                                      29

  6. 4 Directories
       -----------

There are two types of files, system and user.

System files are held in the \OZGIS directory and can be specified as input
files by putting '*' on the front of the file name.

For example, giving a device file as *C256SV3 is the same as giving it
as \OZGIS\C256SV3


User files can be in any directory but it

MUST BE ON THE SAME DISK AS \OZGIS !!!

Hence the \OZDEMO directory is set up on the same drive as \OZGIS

The usual procedure when starting a mapping project is to set up a new
directory, copy all data files to that directory and then use all the
OzGIS programs in that directory.
Setting the directory is done when you define the program to WINDOWS.



                                                                      30
                    7. DEVICE FILES
                       ============



Device files control the appearance of maps:

     . polygon colours and type of fill
     . text colours, sizes and fonts
     . line colours and styles
     . sequences of class colours or hatch patterns
     . menu and message colours

Experience showed that it is better to have fixed sets of definitions rather
than allow the user to specify the display parameters.

Remember that the basic display definition (number of pixels, lines and colours)
was specified when configuring the system.

There are sets of device files available:

     . 256 colour sets (older 16 colour sets for DOS have been withdrawn)
     . sets for standard maps and for bivariate maps
     . coloured polygon fill or hatching or colour simulation

The supplied files have a naming system e.g.

      *C256SV5  is a 256 colour single variate device file
      *B256BV2 is a 256 colour bivariate device file



The best way to understand device files is to look at the contents, for
example:

Select INTERACTIVE DISPLAY AND ANALYSIS from the top menu.

Select the option to CHANGE DEVICE FILE

Type "L" to get a list of the device files that are available.

First look at a 16 colour device file
--------------------------------------

Give the file as *WINSV

Select the option to DISPLAY DEVICE CHARACTERISTICS

You will now get a display that shows the text types (sizes and colours),
lines (types and colours) and the various polygon fills as rectangles.

Of particular interest are the class colours. The bottom set is a sequence of
121 colours which is designed to give the appearance of increasing attribute
values. In this device file for a 16 colour board the colours are in blocks,
but for 256 colour boards all the colours will be different (and can be used
for "continuous colour" maps). The set of colours above are a 7 x 7 set for
bivariate maps. They actually map onto the same set as for single variate maps,

                                                                      31
so if bivariate maps are to be produced different device files should be used.

Now choose a bivariate device file *WINBV and display that.

The bivariate sequence will show a progression of colour in each dimension
(with some missing).

There were a set of files for 16 colour displays, for the DOS version of OzGIS
but under WINDOWS where colours are simulated it makes more sense to use
the set of 256 colour device files. The exceptions are the WINSV and WINBV
files which use the hardware colours used by the WINDOWS system.

Next 256 colour files
---------------------

There is a set of files *C256SV1 to *C256SV9 and *C256BV1 to *C256BV3 for 256
colour boards. Now display one of these. The colour sequence will now be the
complete 121 colours. If you have a standard 16 colour VGA board the colours
will be approximated (dithered) by the WINDOWS graphics software.

Super VGA boards can display the full colour set, but as it does not appear to
be possible to replace the default set of colours in the hardware colour table,
16 colour device files can not display the given set of colours.

Next hardcopy device files
-------------------

Other device files are also available, primarily for display on printers and
plotters, but these can also be used on the display; try them!

*HATCHSV1 is for display of hatched single variate maps and *HATCHBV1 for
bivariate maps.

There is also a series of files CSIMSV1 ......, CSIMBV1... that were designed
to simulate colours sequences on plotters.


DEFAULT.DEV default device file
-------------------------------

You should now display a few of the single variate device files
(*C256SV?) and decide on one that you will use as the default device file.

When you have decided on the default file type exit from OzGIS and:

cd \ozgis
copy C256SV6.DEV DEFAULT.DEV  (using the file you have chosen)

This will overwrite the device file that was supplied as the default with the
system. Obviously you can select a different device file for display at
any time, and you should do so for bivariate maps.

Colour sequences
----------------

The colour sequences are designed to provide a colour progression that can
help interpret the pregression in values in the attribute data.


                                                                      32
The sequences were generated by sampling at equal intervals along curves
through uniform colour space, and then transforming the values using a
model for the colour response of colour / TV monitors.

                                                                      33
                    8. OzGIS MAP TYPES
                       ===============



This chapter introduces  the various types of maps and diagrams that can be
displayed by the OzGIS program.




  8. 1 Map Types
       ---------

Several types of maps and diagrams can be displayed with OzGIS.

Select INTERACTIVE DISPLAY AND ANALYSIS from the top menu

DISPLAY ZONES FOR AN ATTRIBUTE FILE
DISPLAY LINES FOR AN ATTRIBUTE FILE
DISPLAY SITES FOR AN ATTRIBUTE FILE
DISPLAY BIVARIATE ZONES FOR TWO ATTRIBUTE FILES
DISPLAY BIVARIATE LINES FOR TWO ATTRIBUTE FILES
DISPLAY BIVARIATE SITES FOR TWO ATTRIBUTE FILES
DISPLAY ZONES & LINES FOR TWO ATTRIBUTE FILES
DISPLAY ZONES AND SITES FOR TWO ATTRIBUTE FILES
DISPLAY GEOGRAPHIC FILES (NO ATTRIBUTES)
DISPLAY ATTRIBUTE FILES (DIAGRAMS)
DISPLAY A SAVED-DISPLAY FILE
DISPLAY A PRESENTATION FILE



  8. 2 Attribute maps
       --------------

     There are one or two streams of attribute processing for the types of
maps available for zone, line and site attribute data:

     -  zones map
     -  lines map
     -  sites map
     -  two zone streams i.e. bivariate maps
     -  two line streams
     -  two site streams
     -  zones and lines
     -  zones and sites

The type of map is selected before display and cannot be changed except
by returning to this main menu.

Site data can be displayed in several ways:
      . as sized symbols, where additional files of points can be display
        in one of 4 symbols and colours
      . as first symbol using class colours
      . as contour map (WINDOWS)
      . as contour map and class coloured symbols (WINDOWS)

                                                                      34
      . as first symbol using the 4 symbol colours

Line data can be displayed in several ways:
      . as line patterns, where additional files of line can be display
        in one of 4 line types and colours
      . using class colours
      . using the 4 line colours

Basic choropleth maps have already been demonstrated. These are selected
within OzGIS by DISPLAY ZONES FOR AN ATTRIBUTE FILE. You can display maps
with sized symbols in a similar way via DISPLAY SITES FOR AN ATTRIBUTE FILE, and
maps using different line types using DISPLAY LINES FOR AN ATTRIBUTE FILE.

Here are some more examples... Remember you can type "L" to get a list of
files when asked for a file name.

  8. 2. 1 Bivariate zones map Example
          ---------------------------

Bivariate maps enable you to compare two variables. For example you may
want to compare your sales figures with Census data for the type of people
you think are your customers.

Select DISPLAY BIVARIATE ZONES FOR TWO ATTRIBUTE FILES from the main menu.

Use attribute files LOWE1 and LOWE2 and geographic file LOWE (both
attribute files can be the same i.e. you only need one file).

 Note the form of the legend; the primary attribute (first file, top
description) is the vertical part of the legend.

The main mapping menu will now appear on the toolbar:

Attributes
Class
Features
Overlays
Regions
Analyse
Save

These are the major groups of options and will be descibed in later
chapters.

Use "Prev Main Menu" to return to the top menu.

  8. 2. 2 Zones & sites Example
          ---------------------

This type of map is for applications such as deciding where to put shopping
centres, where different symbols can be used for e.g. existing centres,
centres owned by different retail chains and proposed new centres.

This example shows that type of map and also how the geographic data displayed
on a map can be extended and modified.

Select DISPLAY ZONES AND SITES FOR TWO ATTRIBUTE FILES from the top menu.


                                                                      35
Select DISPLAY SITES AS SIZED SINGLE COLOUR SYMBOLS

Use the LOWE1 and LOWE2 attribute files again, and the LOWE zones geographic
file.

Give the sites geographic file as LOWE-S1.

This displays a file with polygons coloured for one attribute and symbols
sized for the other. Now we can add more sites.

Choose MAP REGIONS from the map menu, which shows a menu:

CHANGE THE DISPLAYED ITEMS IN THE MAP
CHANGE MAP REGION WINDOW (GEOGRAPHIC AREA)
ZOOM MAP REGION WINDOW ABOUT X-HAIR POINT
CHANGE MAP REGION VIEWPORT (SCREEN AREA)
DEFINE NEW REGION FOR QUANTISED ZONES
DEFINE NEW REGION FOR QUANTISED SITES
DISPLAY MORE QUANTISED ZONES ON A REGION
DISPLAY MORE QUANTISED SITES ON A REGION

and then DISPLAY MORE QUANTISED SITES ON A REGION. Give the next sites
geographic file as LOWE-S2. Use symbol number 2 (number one is already used).

You will have a coloured zones map with different sized symbols according to
the attribute values and different symbols for the two files.

Select "Top menu" from the Files menu.

  8. 2. 3 Geographic (GIS) maps Example
          -----------------------------

Maps can be displayed that show geographic data without attribute data i.e.
polygons, lines, names at points and symbols at points.

Hence you can display roads, town locations, soil polygons etc.

Where the data are preclassified, feature codes can be used to subset the files
for display.

For example, display some of the Hawaii DLG files. These files came from the
USGS, and after some cleaning up, were entered as DLG-3 data and the polygons
formed using BUILD TOPOLOGY FROM LINE SEGMENTS.

This example will display several of the files and show how feature codes
can be used to subset the data displayed.

Select DISPLAY GEOGRAPHIC FILES (NO ATTRIBUTES) from the top menu.

The next menu allows you to define a map according to the main file of
geographic data that you have. You can add other data to the map as overlays
later:

DISPLAY LINE SEGMENTS FROM A GEOGRAPHIC FILE
DISPLAY MARKERS AT POINTS FROM A GEOGRAPHIC FILE
DISPLAY NAMES AT POINTS FROM A GEOGRAPHIC FILE
DISPLAY POLYGONS FROM A GEOGRAPHIC FILE
DISPLAY LINE SEGMENTS FOR FEATURE CODES

                                                                      36
DISPLAY MARKERS AT POINTS FOR FEATURE CODES
DISPLAY NAMES AT POINTS FOR FEATURE CODES
DISPLAY POLYGONS FOR FEATURE CODES


Select DISPLAY POLYGONS FROM A GEOGRAPHIC FILE and use file HAWDLGWB, which is
the outlines of the islands. Use any polygon number, give some text for the
legend (e.g. "Islands") and use the no boundaries default.

The main menu now appears for this type of map:

OVERLAY LINE SEGMENTS FROM GEOGRAPHIC FILE
OVERLAY MARKERS FOR SITES IN GEOGRAPHIC FILE
OVERLAY NAMES FOR SITES IN GEOGRAPHIC FILE
UNDERLAY POLYGONS FROM GEOGRAPHIC FILE
OVERLAY LINE SEGMENTS FOR FEATURE CODES
OVERLAY MARKERS FOR SITES FOR FEATURE CODES
OVERLAY NAMES FOR SITES FOR FEATURE CODES
UNDERLAY POLYGONS FOR FEATURE CODES
DEFINE MAP REGIONS#
CHANGE LEGEND
DISPLAY TEXT
SAVE DISPLAY AS A FILE


Select UNDERLAY POLYGONS FOR FEATURE CODES.
Use file HAWDLGAB  which is administrative boundaries. The file has feature
codes in the range 900103 to 900108. Give the range as 900103 to 900103 and use
polygon number say 4.  Repeat for another feature code range and polygon
number.

You will notice that a new menu item REMOVE POLYGONS UNDERLAY appears. A
feature of the OzGIS system is that menus are dynamic and reflect the current
status.

The administrative boundaries go outside the island coastlines so you may want
to redraw the island outlines by overlaying line segments for file HAWDLGWB:

Select OVERLAY LINE SEGMENTS FOR FEATURE CODES.
Use file HAWDLGRD which is roads.  The file has feature codes in the range
2905001 to 2905041.  Select a subset e.g. 2905000 to 2905020.
Give the legend text as "roads".

Select OVERLAY LINE SEGMENTS FROM GEOGRAPHIC FILE.
Use file HAWDLGST which is streams. Give the legend text as streams.

Select OVERLAY NAMES FOR SITES IN GEOGRAPHIC FILE. Give the file HAWDLGWB.  The
polygon names will be displayed (the area numbers from the DLG file). Usually a
points file would be used that has the actual names.

Select DISPLAY TEXT, type in a title e.g. "HAWAII", and position it at
the top of the map.

Note that if you regenerate the map the polygons are drawn first, and then line
segments, symbols and finally names.  Within each type they are displayed in
the order specified.  If a mistake is made overlays can be removed.

If polygons overlap, "polygon overlay" operations can be simulated by

                                                                      37
displaying using hatching. e.g. select the hatch device file *HATCHSV1 from
the main menu and then display polygons from the two files HAWDLGWB (the
islands) and HAWDLGAB (administrative boundaries).

Use "Prev Main Menu" (twice) to return to the top level geographic map menu.

A similar set of options are available for overlaying data on other types of
maps. For example you may want to overlay roads or town names on a Census
data map.

  8. 2. 4 Diagrams Example
          ----------------

Distributions, sorted values and quantisation results can be displayed as full
screen diagrams for one or two attribute files. Scatter diagrams can be
displayed for two files.

For example, to display two histograms for two attributes:

Choose DISPLAY ATTRIBUTE FILES (DIAGRAMS) from the top menu.

A menu appears that enables you to choose the type of diagram:

DISPLAY VALUES HISTOGRAM FOR AN ATTRIBUTE FILE
DISPLAY QUANTISATION HISTOGRAM FOR AN ATTRIBUTE FILE
DISPLAY DISTRIBUTION HISTOGRAM FOR AN ATTRIBUTE FILE
DISPLAY VALUES HISTOGRAM FOR TWO ATTRIBUTE FILES
DISPLAY QUANTISATION HISTOGRAM FOR TWO ATTRIBUTE FILES
DISPLAY DISTRIBUTION HISTOGRAM FOR TWO ATTRIBUTE FILES
DISPLAY SCATTER DIAGRAM FOR TWO ATTRIBUTE FILES


Choose DISPLAY DISTRIBUTION HISTOGRAM FOR TWO ATTRIBUTE FILES

Use LOWE1 and LOWE2 files.

Next choose CHANGE DISPLAY FEATURES from the main menu.

Now add some statistics lines:

Choose ADD STATISTICS TO DIAGRAM. A new menu appears:

DISPLAY MEAN & STD DEVIATION
DISPLAY MEDIAN
DISPLAY REGRESSION POLYNOMIAL (for scatter diagrams)
REMOVE STATISTICS DISPLAY

Try the DISPLAY MEAN & STD DEVIATION option (and others if you like).

Now use the Esc key to return to the main diagram menu.

You can change attributes and quantisation in the usual ways.

By now you will have realised that there are many options available down
a multitude of menu paths. This can initially be confusing.

Always remember that if the current menu does not show an option for what
you want to do, simply keep going up a level until you find a menu option

                                                                      38
that seems to offer what you want.

  8. 3 Presentations
       -------------

This option enables a set of saved display files to be defined for
demonstrations.

An Ascii file is set up that gives the names of the saved display files and
menu lines that are associated with them.

The format of these files is explained in a later chapter.

  8. 4 Saved-display files
       -------------------

When you have prepared a map and have it displayed you can use the
SAVE DISPLAY FEATURES option in the map display menu to store all information
about the map in a file. There are two forms. One saves just the map definition
while the other saves a screen image as well.

Both forms enable a map to be restored for further mapping. This is the usual
procedure if a map has taken a long time to design.

Saved maps are also used for hard-copy generation.

  8. 5 Time Lapse Display (not available)
       ----------------------------------


This option was not ported from the PDP11 / DeANZA version.

Special options are available for the display of time lapse files.  The
following parameters can be altered:

      -  The time interval between successive attributes (given in units of
         approximately seconds)

      -  The time interval between the end and beginning attributes of a
         sequence (given in units of seconds); i.e. the pause between a
         repeated sequence.

      -  The beginning and end attribute of the sequence being displayed.

The zone legend format is not updated during a time lapse sequence, and by
default the class description of the legend is set to the "HIGH" and "LOW"
format.  Histograms and scatter plots cannot be displayed during a time lapse
presentation.

                                                                      39
                    9. ATTRIBUTE SELECTION
                       ===================



Attribute data is held in attribute files. Each file can have many variables
e.g. USA Census data STF1A files can have over 900 variables.

This chapter explains the options used to select which attribute is to be
displayed on a map.




  9. 1 Introduction
       ------------

Various attribute files can be nominated to generate a map display.

Attribute may be selected for quantisation and display from attribute
files in various ways:

To try these options, display a zones map using attribute file LOWE1 and
geographic file LOWE as before and then select CHANGE ATTRIBUTES.

The menu gives the following options:

SELECT FROM A LIST
DISPLAY THE NEXT SEQUENTIAL ATTRIBUTE
SELECT AN ATTRIBUTE FOR DISPLAY BY NUMBER
SELECT AN ATTRIBUTE FOR DISPLAY BY DESCRIPTION


  9. 2 From a list
       -----------

A list of available attributes is displayed and one is selected by double
clicking with the mouse.


  9. 3 Sequentially
       ------------

This option will simply select the next attribute off the file.

  9. 4 By number (position in file)
       ----------------------------

A particular attribute may be selected by the position within the file. Type
zero to generate a list of the attributes on the current file.

  9. 5 By attribute description
       ------------------------

The attribute can also be selected by typing part of the description e.g.
"FORC" to retrieve "ARMED FORCES". Typing L lists the attributes.

                                                                      40

  9. 6 By arithmetic operation
       -----------------------

This option enables a new attribute to be generated for display

e.g. the expression " #2 + #4 " forms a new attribute that is the sum of
the second and fourth attributes on the input file.

Attributes can also be prepared as a data preparation option and the options
are fully described in the relevant chapter.

  9. 7 Zone/Site/Line names
       --------------------

It is your responsibility to ensure that the names referenced by the
attributes match the names of the displayed zones, lines or sites in the
map.  Obviously colours can be assigned only to the zone with names common
to the attribute and zone files etc.

Only some of the names have to agree; it is quite common to process attribute
data for a larger area than is displayed.

                                                                      41
                   10. QUANTISATION
                       ============



Quantisation is the process of assigning map items to classes according to
their attribute values.

The quantisation process is the most important aid for the analyst in
understanding the features of the attribute data.  The quantisation method
and parameters should be chosen logically according to the purpose of
analysing the data.

The aim is to display the map that best shows the spatial features and
distribution of the data.







 10. 1 Introduction
       ------------

Attributes are usually presented to OzGIS as values which have to
be quantized into a number of classes for display.

A maximum of 10 classes can appear in single variate zone displays and
9 classes (a maximum of 3 per variate) in a bivariate display.  A maximum
of 4 classes is available for lines and 4 classes for sites.

The best maps usually have a small number of classes; manipulate the
map to show the data according to requirements. This contrasts with the
production of atlases, where large numbers of colours are used as the purpose
to which the map will be put is not known.

To try these options, display a zones map using attribute file LOWE1 and
geographic file LOWE as before, and select DEFINE QUANTISATION.

The quantisation menu has the following form:

CHANGE THE QUANTISATION METHOD
CHANGE THE NUMBER OF CLASSES
SELECT THE ZONES FOR QUANTISATION
SELECT THE ATTRIBUTE VALUE RANGE FOR QUANTISATION

You will find that this menu is dynamic as usual. You will find other
entries such as SELECT THE LINES FOR QUANTISATION or
CHANGE THE NUMBER OF SITE CLASSES for different types of maps.

Try changing the number of classes first and then work through
the various methods.

There are other options to change the list of zones to which quantisation is
applied and to change the range of values over which the method operates.

                                                                      42

 10. 2 Quantisation Methods
       --------------------

Selecting the menu option CHANGE THE QUANTISATION METHOD will display a new
menu of the form:

USE EQUAL VALUE INTERVALS
USE QUANTILES
USE SELECTED CLASS INTERVALS
USE SELECTED NUMBER OF ZONES PER CLASS
USE REFINED EQUAL VALUE INTERVALS
USE THE MEAN AND STD DEVIATION METHOD
USE THE NESTED MEANS METHOD
USE THE NATURAL BREAKS METHOD
USE SELECTED PERCENTILES
USE SELECTED CLASS RANGE PERCENTILES
USE INTERACTIVE SELECTION OF CLASS INTERVALS
USE EQUIVALENCE CLASSES
USE CURRENT CLASS RANGES
USE CURRENT NO PER CLASS

If you have a 256 colour display the following item also appears:
USE PSEUDO CONTINUOUS-COLOUR

You should try out these various methods e.g. with the attribute and
geographic files OZ.



The following methods for quantization are available for determining
the class intervals:

   (a)  Equivalence Classes:  numbers are assigned to the attribute values
        (possibly with integer round-off).  The attribute values should lie
        in the range of the maximum number of classes permitted but they
        will be scaled for the selected number of classes.

        This method enables the quantisation to be carried out on another
        system and the resulting class numbers entered instead of attribute
        values.  A common use is for mapping discrete data e.g. political
        parties on election maps.

   (b)  Quantiles:  intervals are computed by assigning the same number of
        zones to each class.

        This method has often been used to generate choropleth maps, e.g.
        deciles.  The effect of equal numbers of zones is maps that have
        approximate equal areas of each class colour.  Such maps are
        pretty.  Unfortunately quantiles tend to obscure the distribution
        of the attribute data.  (Conversely its a great method if your
        data is of doubtful value)

   (c)  Equal Value Intervals:  intervals are computed from equal
        increments over the range of attribute values.

        The default quantisation method selected when a map is first

                                                                      43
        generated is equal value intervals.  The advantage of this method
        is that the number of zones assigned to each class indicate the
        distribution of the data.  It is recommended for general purpose
        maps and for initial investigations of attribute data.

   (d)  Refined Equal Value Intervals:  intervals are computed from equal
        increments over the attribute value range, modified by a
        "round-off" procedure (e.g. an increment of 10.12 would become
        10.00).

        Maps for publications usually have 'nice' values in the legend.

   (e)  Continuous Colour:  121 intervals are computed from equal
        increments over the range of attribute values.  Only 8 classes are
        displayed in the legend, but the colours are assigned over the 121
        quantized values to give a "continuous colour" appearance.
        This option is only available with standard zone maps on 256
        colour display systems.

   (f)  Interactive Selection of Class Intervals:  intervals are selected
        by the user by placing crosshairs on a displayed histogram.
        (256 colours interactive mode only!)

   (g)  Mean and Standard Deviation:  intervals are determined by dividing
        the range of attribute values at the mean value and at specified
        offsets from the mean that are multiples of the standard deviation
        of the data.  The number of classes must be even.

        This method has particular application for attribute data from
        random populations where the data are expected to have a normal
        distribution and hence statistical theorems govern percentages of
        population within the classes.

   (h)  Nested Means:  intervals are determined by iterative division of
        the range of attribute values at the mean value of the subdivision.
        The number of classes must be 2, 4 or 8.

   (i)  Natural Breaks:  intervals are determined by iterative division at
        the largest difference between attribute values.  The number of
        attribute values between differences is user-specified.  Hence
        class intervals occur at "jumps" in the data.

   (j)  Specification of Class Intervals:  interval values (for a specified
        number of classes) are typed in by the user.

        Hence data within certain value ranges can be isolated.   Suitable
        class intervals for hard-copy maps can be selected.

   (k)  Specification of Numbers Per Class:  intervals are determined by
        user-specification of the number of zones or sites in each class.
        The numbers need only be given for some of the classes; the
        remaining zones or sites will be distributed over the remaining
        classes during each quantization.

        An analyst can isolate data at the extremes of the attribute
        distribution by using this method.

   (l)  Class Number Percentiles:  intervals are determined from

                                                                      44
        user-specified values giving the percentages of the number of zones
        within each class.

   (m)  Class Range Percentiles:  intervals are determined from
        user-specified values giving the percentage of the total range of
        attribute values in each class.

   (n)  Current Class Intervals:  the intervals (and number of classes) are
        used to quantize subsequent attributes.

        Hence a series of maps can be produced with the same legend which
        enables attributes to be compared.

   (o)  Current Numbers:  the number of zones or sites per class (and
        number of classes) are used to determine the intervals for
        subsequent attributes.

 10. 3 Quantisation Ranges
       -------------------

The range of values over which the quantization is applied can be
restricted in all methods.  The following options are available for
limiting the range:

      -  the extremes of all values (default)
      -  user-specified limits (the user enters the low and high values)
      -  refined values (i.e., automatically rounded to "nice" values)
      -  limits fixed at current values for subsequent quantisations

Zones with values outside these limits are assigned the "excluded zone"
value and colour, lines and sites are not displayed.

The menu is of the form:

QUANTISE FOR ATTRIBUTE VALUE RANGE
TYPE IN ATTRIBUTE VALUE LIMITS FOR EVERY QUANTISATION
FIX LIMITS AT CURRENT VALUES
QUANTISE FOR AUTOMATICALLY SELECTED VALUE LIMITS


For example a standard legend for percentage data with value ranges
0,25,50,75 and 100 could be generated by choosing extremes to be 0 and 100
and fixing them, and by using 4 equal value classes.

 10. 4 Quantisation Lists
       ------------------

Each of the attribute processing streams has an associated list
that holds the names of the items being quantised i.e. zones or lines or
sites.  There is one list for a single stream, one zones list for bivariate
maps, and for two streams there is a list of zones and a list of lines or
sites.

Each list selects the items that are to be quantised from the
corresponding attribute file.  When a map is generated the lists are set to
all the names if the attribute files (common names in the case of bivariate
maps).


                                                                      45
Zone lists can be reset to:

      -  all zones in current attribute file (single variate)
      -  all zones common to two attribute files (bivariate)
      -  the displayed zones
      -  zones in a names file

The menu is of the form:

QUANTISE FOR DISPLAYED SITES
QUANTISE FOR ALL SITES IN THE ATTRIBUTE FIL
QUANTISE FOR SITES IN A NAME FILE
EDIT SITES USED FOR QUANTISATION


Zone lists can also be modified by adding or deleting zone names by
typing in a name or selecting the zone with the cursor (256 colour mode)

Site lists and line lists can be modified by giving the names.

Hence the quantisation can take place for a set of items that is
independent of the displayed, zone lines and sites (although it is
illogical for none to be the same).  It is common for the quantisation to
be carried out over a larger geographic area than that being displayed.
Sometimes zones are removed because the attribute data are doubtful e.g.
Census districts with a low population.

Changing attribute files does not change the items whose values are
quantized.

                                                                      46
                   11. GEOGRAPHIC OVERLAYS
                       ===================


This chapter describes how geographic data such as roads and town locations
can be overlayed on top of displayed maps.





 11. 1 Introduction
       ------------

Geographic files can be displayed on zones, sites and lines maps to add extra
information, usually for "navigation" purposes.

Overlays are selected by choosing DEFINE GEOGRAPHIC OVERLAYS off the main
map display menu.

A menu appears of the following form:

OVERLAY LINE SEGMENTS FROM A GEOGRAPHIC FILE
OVERLAY MARKERS FOR SITES IN GEOGRAPHIC FILE
OVERLAY NAMES FOR SITES IN GEOGRAPHIC FILE
UNDERLAY POLYGONS FROM GEOGRAPHIC FILE
OVERLAY LINE SEGMENTS FOR FEATURE CODES
OVERLAY MARKERS FOR SITES FOR FEATURE CODES
OVERLAY NAMES FOR SITES FOR FEATURE CODES
UNDERLAY POLYGONS FOR FEATURE CODES

This menu is similar to the one used with geographic (no attributes) maps.

Polygons can be displayed underneath, such as postal districts under a sites
map.

Lines are often displayed on top of a map e.g. roads, rivers.

Points can be displayed as symbols e.g. locations of shopping centres.

Point labels can also be displayed e.g. names of towns.

Overlays etc are displayed in the order polygon underlays, then the standard
map according to attribute values, then line overlays, then point symbols, and
finally names.

Within each type of overlay display takes place in the order the overlays are
defined. In some cases order of definition is important as a later overlay can
obscure an earlier one.

The basic geographic files contain  polygons,lines, points and names. e.g. a
file of one level of census boundaries (e.g. blocks) could be displayed as a
lines overlay. Files built with BUILD TOPOLOGY also contain approximate
centroids of zones with labels being the zone names.

                                                                      47

 11. 2 USA Census / TIGER Overlays Example
       -----------------------------------

Some sample files are supplied with the system for Washington DC. These were
supplied by the US Census Bureau, and would usually be obtained on CD-ROM.

The attribute file is WASHTRACT and was created by entering the first file off
the STF1A CD-ROM (the original file was called STF1A0DC.DBF). This file
contains about 40 of the 1990 Census variables extracted for tract/BNAs.

Three geographic files are supplied. These came from the CD-ROM files for
Washington DC. The files for records type 1 (endpoints) and type 2 (shapes) were
processed. The files were simplified (thinned) to reduce the size.

WASHTRACT was created by extracting census boundaries for the tract/BNAs with
the IMPORT DATA FILES option, thinning with the PREPARE DATA FOR DISPLAY option,
and finally using the BUILD TOPOLOGY option.

WASHRAIL is a lines file of railroads created by  extracting for feature codes
200 to 252 in the data entry process.

WASHROAD is a lines file of all roads created by extracting for feature codes
100 to 148 in the data entry process.


These files can be used to demonstrate the use of overlays:

First select DISPLAY ZONES FOR AN ATTRIBUTE FILE to display a zones map using
attribute file WASHTRACT and geographic file WASHTRACT. This gives a standard
choropleth map for 1990 Census data for Washington at tract/BNA level.

Select DEFINE GEOGRAPHIC OVERLAYS from the map menu.

A menu appears that offers options for several types of overlays:

OVERLAY LINE SEGMENTS FROM A GEOGRAPHIC FILE
OVERLAY MARKERS FOR SITES IN GEOGRAPHIC FILE
OVERLAY NAMES FOR SITES IN GEOGRAPHIC FILE
UNDERLAY POLYGONS FROM GEOGRAPHIC FILE
OVERLAY LINE SEGMENTS FOR FEATURE CODES
OVERLAY MARKERS FOR SITES FOR FEATURE CODES
OVERLAY NAMES FOR SITES FOR FEATURE CODES
UNDERLAY POLYGONS FOR FEATURE CODES


Now select OVERLAY MARKERS FOR SITES IN GEOGRAPHIC FILE,
use the same geographic file,
select marker 1, give the legend text as TRACTS.


A series of markers will be displayed. The locations are the points within the
standard zones/polygon file built with BUILD ZONES?POLYGONS so are the
approximate centroids of the polygons.

Next select OVERLAY NAMES FOR SITES IN GEOGRAPHIC FILE, and use the same
geographic file in a similar way to display the tract codes. The names here are

                                                                      48
the zone names. You could of course use any file with different locations and
names e.g. town names.

Now add a line segments overlay. Select OVERLAY LINE SEGMENTS FROM A
GEOGRAPHIC FILE. Use the file WASHRAIL to display railroads.

You could now do the same for the roads file. Try subsetting for feature codes
as follows:

Select OVERLAY LINE SEGMENTS FOR FEATURE CODES. Use a different
line number each time and try a range 110 to 138 first to display primary,
secondary and country roads. Then try a range 140 to 148 to display
neighbourhood roads. TIGER file feature codes are defined in the appendix.


                                                                      49
                   12.  DISPLAY CONTROL & MAP DESIGN
                       =============================



This chapter describes the options available for changing the general appearance
of a map.

These options enable map features that are not geographically referenced to be
defined.






 12. 1 Introduction
       ------------

A series of options are available to control the general appearance of maps.

These are chosen by selecting CHANGE DISPLAY FEATURES from the main map
menu.

The menu is of the form:

DISPLAY TEXT
DEFINE ATTRIBUTE DIAGRAMS ON MAP
ADD STATISTICS TO DIAGRAM
CHANGE ZONES LEGEND
CHANGE LINES LEGEND
CHANGE SITES LEGEND
CHANGE GEOGRAPHIC OVERLAYS (GIS) LEGEND
DISPLAY SYMBOL LEGEND
DISPLAY REGION GRIDS

The actual options that appear depends on the type of map. The options are
described in the following sections:


 12. 2  Map Quantisation Legends
       -------------------------


A legend is always displayed on the monitor when an attribute is
quantised for map display.  Similar legends are displayed for zones, lines
and sites.

The menu to change legends has the form:

REMOVE/INCLUDE CLASS RANGES
ANNOTATE CLASS BOXES WITH 'HIGH' AND 'LOW'
TYPE IN CLASS ANNOTATION (2 LINES PER CLASS)
CHANGE ANNOTATION FOR A CLASS
TYPE IN CLASS ANNOTATION HEADER
REMOVE/INCLUDE CLASS ANNOTATION HEADER
REMOVE/INCLUDE NO. ZONES IN CLASSES

                                                                      50
REMOVE/INCLUDE MISSING DATA BOX
REMOVE/INCLUDE EXCLUDED ZONES BOX
REMOVE/INCLUDE UNITS DESCRIPTION
TYPE IN ZONES LEGEND TITLE
REMOVE/INCLUDE ZONES LEGEND TITLE
SPECIFY CLASS RANGE DISPLAY PRECISION
SELECT ZONES LEGEND VIEWPORT WITH THE BOX-CURSORS


The elements of a legend are:

      -  TITLE, a title for the legend (maximum of 3 lines and 16
         characters per line).

      -  UNITS, description of the units of a legend (maximum of 10
         characters).

      -  HEADER, a header for the class annotation (maximum of 8
         characters).  The default is "RANGE".


      -  CLASS ANNOTATION, either

            -  the class intervals as numbers aligned between boxes
               (maximum of 8 characters), or

            -  class description aligned with the centre of boxes (maximum
               of 2 lines, 8 characters per line), or

            -  "HIGH" and "LOW" at the top and bottom of the boxes
               respectively.

      -  EXCLUDED ZONES, annotation for the "excluded zones" class

      -  MISSING DATA ZONES, annotation for the "missing data" class

      -  NUMBERS, the numbers of items in each class.

Zone legends have fixed size boxes that give the colours used for the
classes.

Site legends have variable sized symbols in a special colour that give
the markers and their sizes used for the classes.

Line legends replace the boxes by sample lines in a special colour
that give the line types used for the classes.

All text in a legend is written with small fixed size characters.

Display of the legend elements can be controlled by the user.  The
boxes corresponding to attribute classes are always displayed but the
elements (including "excluded zones" and "missing data " boxes) can be
removed.

Some of the legend text can be replaced by characters entered by the
user on the keyboard, viz.,

         -  title

                                                                      51
         -  units
         -  header
and      -  class description

The default map layout sets the map image viewport as the left three
quarters (approximately) of the monitor, and the legend viewpoints on the
right side of the screen.  The zone legend is on the bottom, line or site
legend above.

New legend viewpoints can be selected with the box cursor.  A single
variate legend may need more than one column to fit.


 12. 3 Overlays (GIS) legends
       ----------------------

When line overlays, markers, text at points or polygon underlays are displayed
a legend appears that describes the overlays. The text must be specified by the
user.

 12. 4 Other Legends
       -------------

When several line files are being displayed using different lines, or
several site files are displayed using different markers, a legend can be
added.

      The line and marker legends have similar format:

      -  a header line of text
      -  legend entries
      -  marker or box in quantisation legend colour
      -  description

 12. 5 Text
       ----

Lines of text can be typed in and displayed on the screen in one of
the four available text types.  The text is positioned with the cursor.  Up
to 20 lines of text can be displayed.

Lines of text can be deleted and moved around the screen.

Text is usually added to a map to supply extra information e.g. the
name of the geographic region and type of zones, organisation names,
disclaimers.

 12. 6 Attribute Diagrams
       ------------------

A menu is available to control diagrams added to an attribute map.

Select DEFINE ATTRIBUTE DIAGRAMS ON MAP.


DISPLAY THE SCATTER DIAGRAM
DISPLAY THE ATTRIBUTE DISTRIBUTION
DISPLAY THE QUANTISATION RESULTS

                                                                      52
DISPLAY THE SORTED ATTRIBUTE VALUES
REMOVE/DISPLAY AXES
REMOVE DIAGRAM
CHANGE DISPLAY VIEWPORT


      (a)  Histograms can be displayed in the map area.  The
           histograms show one of the following:

            -  the number of items (zones or sites) within equal intervals
               of a single attribute
            -  the number of items within class intervals of a single
               attribute
            -  the attribute values corresponding to zones sorted in
               ascending order of attribute value.

               The bars of a histogram are coloured according to the class
               colours in the legend.  For two variate displays, two
               histograms can be displayed one underneath the other.  The
               histograms provide an overview of the statistical
               distribution of the attribute values.

      (b)      Scatter plots can be displayed in the map area for
               bivariate zone displays.  The plots show the distribution of
               zones within the ranges of each attribute.  The elements of
               the plot are coloured according to the class colours in the
               legend.  The scatter plots provide an overview of the
               statistical distribution of the attribute values.

      (c)   Statistics can be added to the diagrams:

      -  mean and standard deviation lines
      -  median

      A regression polynomial of order 1,2 or 3 can be added to a scatter
      diagram.

      The diagram viewport is selected with the cursor.

Addition of a distribution histogram or scatter diagram (bivariate)
add considerably to the information content of a map. They are displayed by
default.

 12. 7 Displayed Colours (removed)
       ---------------------------


Options to change colours are no longer available.

They were removed when DOS limits were exceeded.

All colours within a map display can be changed by the user when a
256 colour VGA display system is being used.  Individual colours can be
selected in three ways:

      (a)  by reference to a colour palette.  The colour is selected with
           the crosshairs (256 colour mode).


                                                                      53
      (b)  by a blue, green and red (B,G,R) triple.  Values for each of the

           elements in the triple range from 0 to 1.0;  a red colour would
           therefore be 0.0,0.0,1.0.

      (c)  by a name from a colour names file.  The name is a character
           string typed on the keyboard.

Any of these ways can be selected by the user.

The set of colours is assigned to map classes and associated map
elements by reference to the current device file.

This enables colours for all of  the classes to be assigned quickly, although
individual colours in the set can be modified subsequently.

Displayed elements must be identified in order to change their
colour.

Certain elements are explictly referenced in the menus associated
with colour change, and can be identified by selecting the appropriate menu
option.  These elements are:

     -  text
     -  markers
     -  lines
     -  zone boundary
     -  map background
     -  excluded zones
     -  zones with missing data
     -  zone attribute classes
     -  background of attribute diagrams
     -  site legend markers
     -  line legend

Specific attribute classes, text, markers and lines are identified by
number.

                                                                      54
                   13. MAP REGIONS
                       ===========



This chapter describes the options that enable the geographic layout of a
map to be defined.




 13. 1 Introduction
       ------------

Map regions enable complex map layouts to be generated.  Maps often
have only one region, typically zones from one geographic file displayed on
the default viewpoint on the monitor.  Multiple regions, each with defined
window and viewport provide many possibilities:

For example:

  . Display of different parts of a country (from different geographic
    files) at the same time.
  . Display of a geographic area and a part extracted from it on the
    same map.
  . Display of overlays such as roads or retail sites on different parts of
    a map.
  . Changing the geographic areas that are currently displayed and moving
    them on the screen.
  . Displaying adjacent geographic areas joined together.

These options are for the geographically referenced features of a map. There
is a different set of options for defining other features on a map such as
text and legends that are simply positioned on the screen.


Definition of map regions is requested by selecting MAP REGIONS from
the main map menu after a map has been displayed.

A menu then appears of the following form:

CHANGE THE DISPLAYED ITEMS IN THE MAP
CHANGE MAP REGION WINDOW (GEOGRAPHIC AREA)
ZOOM MAP REGION WINDOW ABOUT X-HAIR POINT
CHANGE MAP REGION VIEWPORT (SCREEN AREA)
DEFINE NEW REGION FOR QUANTISED ZONES
DISPLAY MORE QUANTISED ZONES ON A REGION
DELETE QUANTISED ZONES FROM REGION

These few options enable comples layouts to be defined (sometimes with a lot
of playing around). If a map is complex it is recommended that the map be
saved often so you will not have to start from the beginning if a
mistake is made.

                                                                      55

 13. 2 Regions
       -------

A new map region is established when a geographic file is displayed.  The
region is defined by the geographic window (or subset) and its displayed
area (or viewport) on the monitor.

A standard map consists of one region. The window is the whole of the
geographic file and the viewport is most of the screen.

Other regions can be added to a map. A maximum of 10 map regions can be
defined in a map. The option DEFINE NEW REGION FOR QUANTISED ZONES enables
other geographic files to be added to the map, each on their own part
of the screen, and to be coloured according to the attribute file values.
For example, you may want to display a map of 5 counties, where you have 5
geographic files (one for each county) and one attribute file that has
the values you want to display. You start by displaying just one
geographic file and then use this option to add and position the other
four files. You will find that it takes some time to finalise the layout
in this type of map.

Regions are identified by number, being the order in which the regions are
defined. A standard map has only region number one, and you do not have to
specify the region number.
A geographic window is initially the total area of the geographic file
(Files are subset as a data preparation process).  You can change the part
of the geographic file that is displayed by selecting a new geographic
extent via the options CHANGE MAP REGION WINDOW (GEOGRAPHIC AREA) or
ZOOM MAP REGION WINDOW ABOUT X-HAIR POINT

A new viewport is selected by positioning the cursor on the monitor with
the mouse or arrows (i.e. it is a rectangular part of the screen) via
the option CHANGE MAP REGION VIEWPORT (SCREEN AREA)

Polygon underlays, line, point and name overlays can be added to any map
region. This process is the same as already described in the chapter on
overlays except that the region number has to be given if there are more
than one.

More than one geographic file can be displayed on a region according to the
attribute data with DISPLAY MORE QUANTISED ZONES ON A REGION. For example
you may want to display maps of two adjoining states. You start by displaying
one of the geographic files for the attribute file in the standard way.
You then add the second file to the same region (and adjust the viewport and
window). The two states will neatly fit together (if the projection &
coordinate system is the same).

Geographic files are automatically windowed, scaled and clipped for
display on map regions.

When multiple files are displayed on a region, the precedure order is
polygons, quantised zones, lines, sites, line overlays, markers and finally
text at points.

Multiple regions can be defined anywhere on the map display area of
the monitor.  However, if regions overlap the display procedure is

                                                                      56
established by the order of definition.  Therefore the user should consider
the order of display carefully in multiple region presentations.

Geographic files can be displayed  in any order, and regions can be defined
and changed as desired.

Many  of these operations destroy the data in the display system memory
(the map display is corrupted) so:
Select "Display map" from the Files menu.


 13. 3 Map List
       --------

A list of displayed items (zones, lines and sites) is maintained by
the system.

The list can be changed by selecting CHANGE THE DISPLAYED ITEMS IN THE MAP,
which displays a menu of the form:

USE THE ITEMS IN A NAMES FILE
USE ITEMS IN THE CURRENT ATTRIBUTE FILE
USE DISPLAYED ITEMS FROM RANGE OF CLASSES
USE THE ITEMS THAT ARE QUANTISED
EDIT THE DISPLAYED MAP ITEMS


The list is sorted into alphabetical order, and the items are
displayed using pixels corresponding to the position in the table (256
colour mode).  This enables items to be selected with the cursor and
identified.

A list of flags corresponding to the map list is also held.  The
flags enable some of the displayed items to be dropped interactively.

The flags are usually set to items in the attribute files:

The options are:

      -  names in attribute file (single variate)
      -  common to two attribute files (bivariate)
      -  names in two attribute files (zones and lines or sites)
      -  names for ranges of classes
      -  names in quantisation lists

Items can be added or deleted by selecting them with the cursor or
typing the name.


 13. 4 Quantised Zones
       ---------------

Up to 10 sets of zones files can be displayed on defined regions.
Adjacent files will automatically join.  GKS clips the polygons to the
edges of the region viewports.  Where regions overlap, the zones of the
last one to be displayed will overwrite the displayed data underneath.

Zones that are not in the map list are not displayed.

                                                                      57

When the system operates in fast interactive mode the zones are
displayed once and the colours changed for the quantisation results.  In
polygon fill mode the zones are displayed every time attribute data are
quantised using fill (colour, pattern or hatch) for the appropriate
classes.

Note that OzGIS expects overwriting to occur.  Hence display of
polygons on top of others is not successful using hatching on plotters,
so OzGIS handles polygons in a special way for this case.

 13. 5 Quantised lines
       ---------------

Up to 10 sets of lines can be displayed on regions.  GKS clips lines
to region viewports.

Lines that are not in the map list are not displayed.

Each file is assigned to a different line, and is displayed in that
line colour.  Four different lines are available.  The results of the
quantisation are displayed by using different line types.

The attribute data can be quantised into up to four classes, so four
line types are used.  The line files are assigned to the four available
lines according to overall classification when they are defined (e.g.
roads, railway tracks and rivers).

 13. 6 Quantised sites
       ---------------

Up to 10 files can be displayed on regions.

Sites that are not in the map list or are outside the region window
are not displayed.

Each file is assigned to a different marker and is displayed in that
marker's colour and background colour.  Four different markers are
available.  The results of the quantisation are displayed as different
sized markers.  When operating in fast interactive mode, the markers are
displayed in bit planes so they can be rapidly cleared.

The attribute data can be quantised into up to four classes so four
different marker sizes are used.  The files are assigned to the four
available markers according to overall classification (e.g. owners of banks
at the sites).

 13. 7 Line Overlays
       -------------

The segments from up to 10 geographic files can be displayed as
overlays on map regions.  Each file is assigned to a region and one of four
available lines and is displayed as a solid line in that line's colour.
GKS clips the lines to the region's viewport.

                                                                      58

 13. 8 Polygon underlays
       -----------------

The polygons from up to 10 geographic files can be displayed as
underlays on map regions.  Each file is assigned to a region and one of eight
available polygon colours.

 13. 9 Marker Overlays
       ---------------

The points from up to 10 geographic files can be used to display
markers at points in regions.  Each file is assigned to a region and to one
of four available markers.  Markers are not displayed for points outside
the region's window.

 13.10 Name Overlays
       -------------

The  points from up to 10 geographic files can be used to display
names at points in regions.  Each site file is assigned to a region and to
one of four available types of text.  Names are not displayed for points
outside the region's window.

 13.11 Map Modification
       ----------------

The window and viewport of a map region can be modified by selecting
a new one with the cursors.

Files displayed for quantisation can be deleted from regions, unless
the only one of that type.

                                                                      59
                   14.  MAP ANALYSIS
                       =============



This chapter describes how you can find out more about the attribute data
displayed on a map.





 14. 1 Introduction
       ------------

Selecting ANALYSE MAP DATA from the main map menu enables further analysis
of a displayed map (with attribute data).

The following menu appears:

INTERROGATE MAP DATA
GENERATE MAP REPORT ON FILE OZGIS.OUT
DISPLAY ATTRIBUTE STATISTICS


 14. 2 Map Reports
       -----------


An option is available to write a full map report (giving details of
the displayed items, their attribute values and class numbers) on the file
OZGIS.OUT


 14. 3 Attribute Data Statistics
       -------------------------


The statistics of displayed attributes can be computed and displayed
under user control.

The following statistics are computed for a simple attribute:

      -  minimum value
      -  maximum value
      -  mean value
      -  median value
      -  standard deviation
      -  skewness
      -  kurtosis

For pairs of attributes (bi-variate displays) the above statistics
are computed for each attribute, as well as

      -  correlation coefficient
and   -  regression polynomial coefficients (to order 3).


                                                                      60

 14. 4 Map Interrogation
       -----------------


When a map has been displayed, it is possible to interrogate the map
data interactively.

The actual menu depends on the type of map, but is of the form:

LIST DATA FOR A CLASS RANGE
LIST DATA FOR NAMES TYPED AT TERMINAL
LIST DATA FOR ITEMS IN A NAMES FILE
LIST DISPLAYED SITES
LIST QUANTISATION SITES
LIST SITES WITHIN WINDOW SELECTED WITH BOX-CURSOR
LIST SITES WITHIN DIGITISED POLYGON
LIST SITES WITHIN CIRCLE, TYPED IN RADIUS
LIST SITES WITHIN CIRCLE, CURSOR SELECTED RADIUS


The details generated by interrogation are the names of the zones,
lines or sites, the values of the displayed attributes (one value for
single variate displays, and two for bivariate) and their assigned class
number.

The map can also be interrogated for the textual information held in text
attribute files. This enables non-numeric information to be accessed in the
same way as the values in standard attribute files.

The options for interrogation are:

   (a)  class number range

        -  items (zones, lines or sites) within a specified range of class
           numbers.

   (b)  single item identification

        -  zone line or site selected by entering its name at the keyboard.

   (c)  set identification

        -  items selected by a names file, items in map, or items in
           quantisation lists.
   (d)  Lists

        -  The names of all the displayed items are held in one list.
           Each attribute stream has an associated list of items that are
           being quantised.

   (e)  Interactive selection

        -  The "box cursor" can be used to describe a rectangular region to
           select items.  The selection of zones and lines is either by
           all minimum bounding rectangles (MBR) of the items that fall
           completely within the cursor window or MBRs that intersect

                                                                      61
           the window.  Sites (and zone centroids) are selected by points
           that lie inside the window.

        -  Map items can also be selected within a circle and for a digitised
           simple polygon.


The list of items selected interactively is also output to a file QUERY.OUT
for use either as a names file or for export to other systems.

                                                                      62
                   15. DATA PREPARATION
                       ================




This chapter describes options to prepare data for display and analysis.





 15. 1 Introduction
       ------------

The raw data are input to the system using IMPORT DATA FILES. However, the
data often need further processing. Also, some data needed within the system
cannot be specified as data files and need to be prepared.

These facilities are provided by the PREPARE DATA FOR DISPLAY option in the
top menu.

The main menu is of the form:

PROCESS ATTRIBUTE FILES
PROCESS GEOGRAPHIC FILES
PROCESS NAMES FILES
OUTPUT EXTERNAL DATA FILES


 15. 2 Attribute Files
       ---------------


The PROCESS ATTRIBUTE FILES menu is:

FORM ATTRIBUTES WITH ARITHMETIC EXPRESSIONS
AMALGAMATE ATTRIBUTE DATA FOR AN COMBINE FILE


A new attribute file can be generated from an attribute file and a
combine file by selecting AMALGAMATE ATTRIBUTE DATA FOR AN COMBINE FILE.

The combine file defines new zones (or site catchments)
in terms of the names referenced by the attribute file.

For example, you may define sales territories in terms of postal districts
and put the definition in a combine file (manually or via OzTerr). You would
then amalgamate both the geographic file of postal district boundaries and
any attribute files based on postal boundaries to produce files for
mapping.



Attributes can also be derived from existing attributes by applying
arithmetic operations to the attribute values via FORM ATTRIBUTES WITH ARITHMETI


                                                                      63
A common application is preprocessing Census data before display to form
the desired attributes.

Attributes are identified by the character # followed by a number,
indicating the sequential position of the attribute on the input file
e.g. #10 represents the tenth attribute).  An example of an expression
to form a composite attribute is:

                 (#1+#2)/2 > 0 < 1000

This creates a new attribute whose values are half the sum of the values
from the first and second attributes on the input file.  Any valid
arithmetic expression is acceptable.  The output values are limited to
the given range.

Functions available are:-

      LOG10  :  common logarithm
      SQRT   :  square root
      ABS    :  absolute value
      EXP    :  exponential
      SIN    :  sine
      COS    :  cosine

Functions removed from the PC version are:

      LOG    :  natural logarithm
      AINT   :  truncation
      TAN    :  tangent
      ATAN   :  arc tangent
      SINH   :  hyperbolic sine
      COSH   :  hyperbolic cosine

Pi is referred to as PI.

Operators are:

   +  addition
   -  subtraction
   *  multiplication
   /  division
   >  greater than or equal to
   <  less than or equal to

Expressions are evaluated left to right and have a limit of 70
characters.  Parentheses should be used to ensure there are no
ambiguities.

The user must give a 30 character attribute description and 10 character
units description for each new attribute that is generated.


 15. 3 Geographic Files
       ----------------

The menu is of the following form:

SUBSET FOR ZONES LIST

                                                                      64
SUBSET FOR LINES LIST
SUBSET FOR SITES LIST#
AMALGAMATE ZONES FOR A COMBINE FILE
JOIN LINE SEGMENTS FOR POLYGONS
SIMPLIFY (THIN) LINE SEGMENTS

Often the geographic region covered by a geographic file will be much larger
than is required. Geographic files can be subset (windowed) on the basis of
a list of required display items (zones, sites, lines).
      - items in a names file
      - items in an attribute file
      - items within a window selected with the cursor from a displayed file

Line segments can be simplified to reduce the number of points that
have to be processed.  This is used to speed up display where the
resolution of the digitised data are higher that that needed for display
terminals.

Line segments that form polygons can be joined together into long segments.
Where many short segments are used this process, in conjunction with
simplification, can sustantially reduce the disk storage required and speed
processing.

The zones in a geographic file can be amalgamated according to a combine
file to generate a new geographic file.  The new file contains the new
zones.  The same combine file can be used to generate attribute data for
the same new zones. For example, you may amalgamate basic Census zones into
zones at a higher level or into sales territories.

 15. 4  Names Files
       ------------

Names files give lists of items (zones, sites,lines) that are to be processed.
These lists can be generated from other types of files. These options are
particularly useful when the names files are to be modified.

The menu is of the form:

SAVE ATTRIBUTE FILE NAMES AS A NAMES FILE
SAVE GEOGRAPHIC FILE ZONES AS A NAMES FILE
SAVE GEOGRAPHIC FILE LINES AS A NAMES FILE
SAVE GEOGRAPHIC FILE SITES AS A NAMES FILE
EDIT A NAMES FILE

For example, you may output the names from a Census attribute file to a
names file, edit it with a word processor and the use it to subset a
census boundary (geographic) file to produce the desired map region.


 15. 5  Output to Data Files
       ---------------------

Options are provided to output internal files as data files so they can be
modified with word-processors for further processing.

The menu is of the following form:

GENERATE ATTRIBUTE TEMPLATE DATA FILE

                                                                      65
OUTPUT NAMES DATA FILE
OUTPUT ATTRIBUTE FILE IN SIMPLE (SAS) FORMAT
OUTPUT COMBINE DATA FILE

Names files can be editted to change the lists of items used for processing.

Attribute files can be output in simple database format.

Combine files can be modified as part of the definition of territories and
sites.

Attribute templates can be generated for preparation of attribute data with
a word-processor. This is also useful for displaying new boundary data when
you have no attribute file. The file can be input as a database
format attribute file.

 15. 6 Palette Files (Removed from system)
       -----------------------------------

Palette files have been removed from the system until display systems with more
than 256 colours are available.

Palettes are generated by selecting colours for the elements of a
palette shown on the screen.  The colours can be selected in the
following ways:

      -  by entering blue, green and red values.

      -  by reference to another palette

      -  by reference to a colour names file

      -  by reference to a colour cross-section displayed in the map area
         of the screen.

After colour selection, the palette can be saved as a file.

   An existing palette file can be modified to produce a new file, by
   displaying it and adding or deleting elements.

 15. 7 Colour Names Files  (Removed from system)
       -----------------------------------------

   Colour names files are generated by typing in a name and then selecting
   the corresponding colour in the ways described above for selecting
   colours for palettes.  An existing colour names file can be modified.

                                                                      66
                   16. BUILDING ZONES FROM SEGMENTS
                       ============================




Geographic data, such as Census boundaries, are often supplied as lines which
have to be connected to form polygons or complex lines.

This chapter describes the BUILD TOPOLOGY option which carries out the
building process and outlines common preprocessing of this type of data.




 16. 1 Use
       ---

Zone boundary data can be supplied either as the complete set of points for the
outsides of each polygon or as the line segments that make up the boundaries.
Most segments will be common to two polygons so only about half the number of
points are required. The segment form also allows zones to amalgamated into
larger zones (by dropping internal segments) and to be thinned (by dropping
excess points).

The segments form of data is preferred to polygon formats.

The build process takes line segments and joins the ends together to form
polygons. The names of the zones on each side of the segments are used to
derive the zone names.

Complex polygons are handled. Zones can be made up of many polygons, both
disjoint polygons and polygons within polygons. The display order of the
polygons are calculated so e.g islands within lakes within zones all appear.

Line segments can also be built into complex lines to which attribute data can
be assigned.

It is usual to line simplify (thin) the segments before building as many
digitised boundary files (e.g. census) are at a much higher resolution than
require for the display. Joining of line segments and further thinning may
follow.

If the message"TOO MANY POINTS IN POLYGON" appears you will have to line
simplify your data.

The building process can use a lot of disk space, effectively the product
of the max number of polygons in a zone and the number of zones. Options
are provided to help control this.

When the line segments were generated from spatial operations, arithmetic
roundoff can produce slightly different endpoints. A tolerance factor can
be given to help join faulty points. The tolerance is usually zero.

                                                                      67

 16. 2 Faulty Digitised Data
       ---------------------

The algorithm assumes that the segments have been produced on a proper
digitising system and are correct e.g. it is assumed that end-points meet and
the segments do not cross. Problems such as repeated segments, missing segments
etc may cause problems. Ensure you use the program with trace turned on. If
necessary turn on debug and look at the OZGIS.OUT file.

Use the file interrogation option to find the statistics on the geographic file
e.g. the number of zones.


The top menu option PREPARE DATA
FOR DISPLAY can be used to generate a prototype attribute file (simple format)
from the zones in the geographics file and hence get some test data that can be
entered via IMPORT DATA FILES to form an attribute file. Displaying both files
via SIMPLE CENSUS-TYPE MAPPING will allow the file to be checked.


 16. 3 Example
       -------

The procedure can be demonstrated with any of the geographic data files:

First input the geographic data file and give it a temporary name:

Use IMPORT DATA FILES from the top menu
Select IMPORT GEOGRAPHIC FILES and then IMPORT A STANDARD FORMAT
GEOGRAPHIC FILE. Use the test data file LOWE-G and give the new file name as
TEMP1.

Next line simplify the line segments to drop points:

Use PREPARE DATA FOR DISPLAY from the top menu
Select PROCESS GEOGRAPHIC FILES and then SIMPLIFY (THIN) LINE
SEGMENTS. The input file is the one just entered i.e. TEMP1 and output the new
one as TEMP2. Simplify according to the size of the final map on the screen
e.g. give a value of 100 to throw away a lot of the data points e.g. if you
have a super VGA at 1024 X 768 you could use 750.

Now build the polygons structure from the lines.
Select BUILD TOPOLOGY FROM LINE SEGMENTS from the top menu

The menu is:

BUILD ZONES FROM LINE SEGMENTS INTO NEW GEOGRAPHIC FILE
BUILD ZONES FROM LINE SEGMENTS INTO NEW DATA FILE
BUILD LINES FROM LINE SEGMENTS INTO NEW GEOGRAPHIC FILE
BUILD LINES FROM LINE SEGMENTS INTO NEW DATA FILE

The usual option is BUILD ZONES FROM LINE SEGMENTS INTO NEW GEOGRAPHIC FILE.

Give the input geographic file as the simplified file TEMP2 and output it as
TEMP3.


                                                                      68
Use the defaults for other questions.
Finally display the result (attribute file LOWE1 and geographic file TEMP3)
by using the INTERACTIVE DISPLAY AND ANALYSIS top menu option.

                                                                      69
                   17. WK1 INTERFACE TO OTHER SOFTWARE
                       ===============================


 17. 1 Introduction
       ------------

The OzGIS system was designed to provide advanced mapping capablilities that
could be interfaced to other systems such as:

 - Database systems for manipulation and retrieval of attribute data
 - Systems for generation of map boundary data
 - Statistical analysis systems with graphic display and reporting facilities
 - Mapping systems with analysis and hardcopy facilities.

The main software systems that are of value are spreadsheets and database
systems for handling attribute and other data. These software systems (e.g.
Lotus, Excel, MS access, Paradox) are easy to use and are growing in
sophistication.

The OzGIS system interfaces to these systems via the Lotus WK1 file format.

Data must be held in a tabular format where the first column is ALWAYS the
primary key and is the same as the map identifiers (and usually alphanumeric)

Other columns depend on the type of data.

WK1 format data can be imported into OzGIS via menu options in the data entry
process and exported via options in the data preparation module.

 17. 2 Attribute data
       --------------

Data from spreadsheets can be both imported and exported in WK1 format.

The spreadsheet must be set up in a fixed format:

The data values are in a matrix with the values for the zones (or sites or
lines) in columns and the different attributes across in the rows.
Values can be missing and can be integer or floating point.

The first column must contain labels which are the 10 character zone (site etc)
names, beginning at row 3. These must be SORTED in ascending order.

The top row contains labels that are the (up to) 30 character attribute
descriptions starting at column 2.

The second row is the 10 character attribute descriptions.
This is recommended but does not have to be present as some systems (e.g. MS
ACCESS) do not support the concept.

e.g. the file DEMO123.dat can be read into the spreadsheet. It should look
like:

                 POPULATION GROWTH   SALES
                 NUMBER              $
ABBOTSFORD                 7418      237

                                                                      70
BURWOOD E                  9925      955
CONCORD                    8984      202
CROYDON N                  9369      298
CROYDON W                   735
FIVE DOCK                  9903      716
HABERFIELD                           727
HOMEBUSH                   6631      704
HUDSONPARK                 4668       71
MORTLAKE                   1725      198
STRATHFIELD                6285      663
YARALLA                    9875      516

For example, with Microsoft Excel for Windows, the test file can be read by
choosing the option "Open" from the "File" menu and giving the test file as
\OZDEMO\DEMO123.WK1. A spreadsheet in the above format can be output by
selecting the "Save As" option from the "Files" menu and using the WK1 format
option.

 17. 3 Names Files (lists of names)
       ----------------------------

The first column of the spreadsheet can be output as a WK1 file and then
imported into OzGIS as a names file to control the processing.

A names file can be exported as a single column WK1 file and hence used to
initialise a spreadsheet.

Names can also be output from a geographic file, where the list is one of the
zone names, line names or site names.

 17. 4 Points
       ------

Site names and their (X,Y) locations can be exported as WK1 files.

Points output from a spreadsheet can be input as a points geographic file. The
columns must have names called exactly "X" and "Y". You can also assign
positive numeric feature codes by a column called exactly "Feature Code". If
the column is used, a feature code must exist for every point (use zero if not
required).

 17. 5 Territories and Catchments
       --------------------------

A combine file containing the definitions of either territories or site
catchments can be exported from OzGISas a WK1 file. The column names are
"Territory" and "Weight" (the first column is the zone name).

 17. 6 Addresses
       ---------

You can export a column called "Address" as a WK1 file from a spreadsheet and
import it into OzGIS for reformatting as a data file that can be used for
geocoding.

                                                                      71
                   18. MAP PROJECTIONS
                       ===============








 18. 1 Introduction
       ------------

The projection options will process a geographic file to form a new
geographic file converting either from (Longitude,Latitude) to a projection
or in the reverse direction.

Often projections will not be of concern, as map data will be used as supplied.
However, if data comes from several sources in different projections, the files
may have to be converted to a common coordinate system.

You will have to have a basic knowledge of the projection you want to use
e.g. that AMG is UTM with the Australian Spheroid and a false origin
(500000,10000000).

The options are based on public domain software from USGS.

Projections processing is initiated by selecting MAP PROJECTIONS from the top
menu
The main menu is:

CHOOSE FROM PROJECTION SET 1
CHOOSE FROM PROJECTION SET 2
CHOOSE FROM SPHEROID SET 1
CHOOSE FROM SPHEROID SET 2
DEFINE NON-STANDARD UNIT
WRITE PROJECTION DEFINITION INTO GEOGRAPHIC FILE
TRANSFORM LAT / LONG FILE TO PROJECTION
TRANSFORM PROJECTION FILE TO LAT / LONG
DISPLAY PROJECTION PARAMETERS FOR GEOGRAPHIC FILE


 18. 2 Precision
       ---------

Vertices are stored in single precision in OzGIS (there is not enough memory on
the PC to do anything else). This means an accuracy of seven digits, so some
values may not be accurate e.g. UTM may be a few metres out.

 18. 3 Latitude / longitude
       --------------------

Latitude / longitude data must be given with units degrees.

Latitudes are negative in the Southern hemisphere.

Usual value ranges are:

                                                                      72
Longitude -180 to +180
Latitude  -90  to +90

Note that the X value in data files is the longitude.

examples: (-100.0,50.0) i.e. longitude -100, latitude 50
          (145.0, -42.0) a point in Tasmania

 18. 4 Projections
       -----------

Several projections are supported:

Albers Conical Egual Area
Azimuthal equidistant
Equidistant Conic
Equirectangular
Gnomic
Lambert Conformal Conic
Lambert Azimuthal Equal Area
Mercator
Miller Cylindrical
Orthographic
Polyconic
Stereographic
Transverse Mercator
Sinusoidal
State Plane (USA) (NOT SUPPORTED YET)
Universal Transverse Mercator
Van der Grinten

 18. 5 Ellipsoids
       ----------

Several spheroids are available. The default is either Clarke 1866 or the
6370997 metre sphere where a radius is asked for.

MERIT 1983
GRS 1980(IUGG, 1980)
IAU 1976
Airy 1830
Australian Natl, S. Amer., IAU 64
GRS 67(IUGG 1967)
Bessel 1841
Clarke 1866
Clarke 1880 mod.
Everest 1830
Hough
International 1909 (Hayford)
Krassovsky, 1942
Mercury 1960
Modified Airy
Modified Everest
Modified Merc 1968
New International 1967
Southeast Asia
Walbeck
WGS 66

                                                                      73
WGS 72
Sphere of 6370997 m

 18. 6 Use
       ---

The parameters of the projection are stored in the geographic file. When the
data are first entered the projection is usually set to 'undefined', unless it
is known e.g. Census boundary data are usually set to geographic (lat/long
units degrees) by the data entry process.

The first operation is often to define the projection of a new geographic file
and store the parameters in the file header. Hence you have to
choose the projection, spheroid if non-standard, and then the option
WRITE PROJECTION DEFINITION INTO GEOGRAPHIC FILE.

Transformation is to and from lat/long. Hence conversion from one projection to
another has to take place in two steps.


 18. 7 Example
       -------

Suppose you have entered a file that you know is UTM for zone
number 20 and you want to convert it to Lambert Conformal.

Select CHOOSE FROM PROJECTION SET 1 from the main menu, and then
select U.T.M. and give the zone number.

Then select WRITE PROJECTION DEFINITION INTO GEOGRAPHIC FILE and give
the name of your file.

Your file will now be defined as UTM by having the file header updated.

Now choose TRANSFORM PROJECTION FILE TO LAT / LONG and give the file names
to generate a temporary file in latitude / longitude from your original file.

Then use CHOOSE FROM PROJECTION SET 1 again and choose LAMBERT CONFORMAL CONIC.

Then using TRANSFORM LAT / LONG FILE TO PROJECTION will give you the
desired file in Lambert Conformal from the lat/long file to a new file.


                                                                      74
                   19. HARDCOPY MAP PRODUCTION
                       =======================



This chapter describes the OzMap program which allows maps to be output to
printers, plotters and files.





 19. 1 Overview
       --------

Maps are designed with the interactive OzGIS program and saved as Saved display
files. These files are then read into the OzMap program and output on the
desired device or file. Attributes and quantisation can be changed in the usual
way to produce a series of maps.

Maps can also be printed directly via the File menu.

Hardcopy map production is limited by the capabilities of the SCIPLOT package.

SciPlot produces many graphic file types:

The Postscript file is an ASCII file that may be edited or sent directly to any
Postscript printer.

The Encapsulated Postscript file (EPS) and the Computer Graphics Metafile (CGM),
an ANSI standard format file, are files that should not be edited for they
contain binary information.  EPS and CGM files can be imported directly into
wordprocessors or other graphical products.

The HP pen plotter file (HPGL) is an ASCII file that can be edited or imported
into wordprocessors or other graphical products.

The WordPerfect file (WPG) is a binary file in WordPerfect's internal graphics
format.  WPG files are directly importable into the WordPerfect wordprocessor.

The SciPlot Graphics file is a file in SciPlot's own internal format and is
used solely as input to the VECTOR program.  This file is a binary file in very
compact format.  It contains the stream of vectors which represent the figures,
characters, etc. generated during the execution of the application program.
VECTOR processes this graphic file and arranges raw vectors in a direction of
paper motion order before display on dot matrix printers and laserjet printers.

For Apple LaserWriters, HP pen plotters, and other graphics devices that
support a vector drawing commands directly, ordering is not required and VECTOR
immediately displays the vectors.

VECTOR's function is to provide a utility to register SciPlot's output on
plotting devices (dot matrix and laserjet printers) which cannot be supported
directly without requiring significant system resources.  VECTOR also provides
interactive preview of graphics files on the screen or bath processing at some
other time.

                                                                      75

 19. 2 Procedure
       ---------

The main menu is:

CHANGE ATTRIBUTES
DEFINE QUANTISATION (CLASSES)
DISPLAY DEVICE CHARACTERISTICS
CHANGE DEVICE FILE
SELECT ANOTHER SAVED DISPLAY FILE
CHANGE DISPLAY DEVICE

You must provide the saved-display file name for a map that was prepared
using OzGIS.

Select "Draw map" from the Files menu to display the map on the current device.
Initially this is the printer, but you can use CHANGE DISPLAY DEVICE to send it
e.g. to a file. The available devices are selected from the menu:

SCREEN
PLOTTER METAFILE (for VECTOR program)
PRINTER METAFILE (for VECTOR program)
POSTSCRIPT ASCII FILE
ENCAPSULATED POSTSCRIPT FILE
HPGL FILE
CGM METAFILE
WORDPERFECT FILE
ONLINE APPLE LASER WRITE,
ONLINE PLOTTER

You can change attributes with CHANGE ATTRIBUTES option and can change the
quantisation with DEFINE QUANTISATION (CLASSES). Thus you can work through
a set of attributes in the usual way.

The option SELECT ANOTHER SAVED DISPLAY FILE enables other maps to be displayed.

 19. 3 Photographs
       -----------

Colour slides can be successfully produced by photographing the screen.

The room has to be dark and any lights on the PC covered. Watch for reflections
around the edge of the screen (blacken around the screen).

You will have to experiment. Initially bracket exposures.

Lenses with long focal lengths reduce the curvature of the screen.

An initial setting is:

250mm lens
200 ISO film
f/8 at 1 second

                                                                      76

 19. 4 OzMap Device files
       ------------------

Several device files are provided to control the appearence of maps on output
devices. These device files can also be used with OzGIS (they will need minor
modification for use with EGAs).

You have to use device files that use hatching for polygon fill. The
configuration section explains the files available. Generally you need to use
hatching device files that have the same resolution as that used in OzGIS or
aspects and character sizes may not be suitable.

HATCHSV1   - provides polygon display using hatching.
HATCHBV1   - hatching for bivariate maps.
CSIMSV* and CSIMBV* - a series of device files that use the red, green and blue
plotter pens (or screen colours) to simulate the colour sequences; look at then
on the screen first to decide which ones to try.

The hatching device files can of course be modified to define other hatching
patterns.

The options DISPLAY DEVICE CHARACTERISTICS and CHANGE DEVICE FILE can be
used to investigate the various device files.


 19. 5 VECTOR Program
       --------------


This program enables metafiles produced in the OzMap program to be output to a
variety of devices and files with such options as rotation and scaling.

Its easier to use than read about!!


VECTOR has two modes of operation, an interactive mode and a batch mode.
The batch mode processes command strings from a disk file.  The user can
include the command filename with the VECTOR command (eg. VECTOR
command.fil).  Alternatively, the user can wait until VECTOR issues a
prompt for the type of interaction desired.  The format of the command
file and a description of the VECTOR.CFG file follows:

VECTOR[d:][path][filename[.ext]] [/U]

[d:][path][filename[.ext]] [/U] - Process file which contains
filenames of graphics files to be processed in batch mode.  These
files will be processed one at a time and plotted on the designated
printer, plotter, or graphics crt device.  As a default, the
VECTOR.CFG file will be searched for a process filename.  When a
filename is specified on the VECTOR command line, the process
filename given in VECTOR.CFG file is totally ignored and replaced by
this new filename.

/U - This update option is used to override all parameters specified
in the VECTOR.CFG file. The option initiates an interactive dialog
with the user to obtain a new set of parameters for VECTOR. The user

                                                                      77
is given the opportunity at the end of the dialog to update the
current VECTOR.CFG file with these new parameters.

VECTOR.CFG Configuration File.

The VECTOR.CFG configuration file contains a list of commands that
define VECTOR processing parameters. Each time VECTOR executes, it
reads and interprets this file. If the VECTOR.CFG file cannot be
located, VECTOR will interact with the user from the terminal to set
up these parameters.

Format of Configuration File Commands:

Cmd    Option        Description

FILE   =CONS         -Get graphics filenames from console.
       =[d:][path][filename[.ext]]- Use this file as a process file
containing graphics filenames.

DEVICE =DOT          -Dot Matrix Printer
       =PEN          -HP Pen Plotter
       =JET          -HP LaserJet Printer
       =WRITER       -Apple LaserWriter Printer
       =CGA          -CGA Color Screen
       =EGA          -EGA Color Screen
       =VGA          -VGA Color Screen
       =HGA          -Hercules Monochrome Screen

PORT   =COM1         -Printer/Plotter on Primary Serial Port
       =COM2         -Printer/Plotter on Secondary Serial Port
       =LPT1         -Printer/Plotter on Primary Parallel Port
       =LPT2         -Printer/Plotter on Secondary Parallel Port

ANGL   =XXX.XX       -Rotation Angle (degrees)
XSCL   =XXX.XX       -X-Axis Scale Factor
YSCL   =XXX.XX       -Y-Axis Scale Factor
XOFS   =XXX.XX       -X-Axis Offset (inches)
YOFS   =XXX.XX       -Y-Axis Offset (inches) <<<<<< e.g. 5.0 for printer

WAIT   =ON           -Wait between Plot Frames
       =OFF          -Do not wait between Plot Frames

[When serial port is used for printer/plotter device, following
commands are valid]:

HAND   =SOFT         -Software Handshake (XON/XOFF)
       =HARD         -Hardware flow control on DSR line

MODE   =195          -Serial Port Mode Set Code, specified in
decimal format. 195 = (9600 baud, no parity,
1 stop bit, 8 bit characters)

- Mode Set Code Description -    [bits]

7     6    5  4     3       2          1       0
--Baud Rate-- -Parity-   -Stop Bits-  -Char Length-
000 -  110   00 - None 0  -    1      10  - 7 Bits
001 -  300   01 - Odd  1  -    2      11  - 8 Bits

                                                                      78
010 -  600   11 - Even
011 - 1200
100 - 2400
101 - 4800
110 - 9600
111 -19200

[When dot matrix printer is used, following commands are valid]:

PINS   =9           -EPSON (MX-80,FX-80,FX-85,FX-850...)
       =24          -RPDON (LQ-800)

HRES   =HIGH        -High Horizontal Resolution
       =LOW         -Low Horizontal

VRES   =HIGH         -High Vertical Resolution
       =LOW          -Low Vertical Resolution

- Printer Resolution Table -

Printer  Resolution   Vertical  Horizontal
9-Pin     LOW           72         120
9-Pin     HIGH          216         240*
24-Pin     LOW          180         180
24-Pin    HIGH          180         360
* 240 dot per inch resolution is not available on MX-80.

[When HP Pen plotter is used, following plotter initialization
command is valid]:

INIT   =ON           -Send handshake init sequence before plotting
       =OFF          -No handshake init sequence required

When a process file is specified, VECTOR will process multiple graphics
files in a batch mode. For the individual graphics file, VECTOR processes
one plot frame at a time, for each file may contain more than one plot
frame.  For dot matrix and HP LaserJet printers, VECTOR first sorts all
the vector records in a minimum Y order for one plot frame.  This sorting
is accomplished by creating an in-memory linked list directory of the
disk records for the frame.  VECTOR accesses the graphics file randomly,
bringing in only those records that contain vectors in the current
process window. These print devices restrict the processing to a paper
movement order. For HP Pen Plotters, Apple LaserWriters, and crt
displays, VECTOR can process the vectors directly without any sorting for
these devices support vector drawing commands.

An inherent difficulty in this sort of processing approach is the limit
imposed by the processor's memory size. There is an upper bound on the
size of the graphics plot that can be handled because the linked list
directory as well as a limited set of the vectors must be memory
resident.  The exact size limit is difficult to predict because it is a
function of the number of records in the file, the density of vectors per
processing window, and the amount of lengthy vectors that must be
remembered over many processing windows.  The VECTOR.OBJ file on the
distribution diskette supports 64KB of directory sort space.  If this is
not enough, a VECTOR.LRG file is included which supports 256KB of
directory sort space.  Please note that the use of the VECTOR.LRG object
file will significantly increase the size of the VECTOR.EXE file.

                                                                      79

Features

The features incorporated in VECTOR are numerous.  Multiple plot frame
processing is automatic.  A graphics vector file may be accessed from any
disk.  Normal FORTRAN I/O is used to read the 128 byte binary records by
the direct access method.  The VECTOR program will respond to a
control-C/Break at any time during execution.  This will terminate the
current processing task, reset the printer to the top of form, and
request another task.  Statistics for each plot frame, as well as total
run statistics are displayed during the execution of VECTOR. For the dot
matrix type graphics printer, four basic resolutions are provided by
VECTOR depending on the type of printer attached.  A low resolution mode
is supported to quickly review the plot with very limited definition.
This mode is useful for quick turn-around. The high resolution mode takes
much more time because of hardware constraints, but gives very
satisfactory results.  VECTOR also has an on-screen preview capability
which allows quick identification of graphics files.

Error Conditions:

During the execution of VECTOR, several error messages might be displayed
on the terminal.  The only message that is not serious has to do with a
premature termination of the programs that produced the graphics output
file. The message reads "Premature End-of-File at Record XXXX". It just
means that the graphics file was not terminated properly, but all the
graphics data is valid.

The second class of messages is serious and should not be ignored. The
messages are listed along with reasons.

"Error reading graphics file" - means that FORTRAN I/O was unable to read
the graphics file. The file should be recreated on another disk to
correct the error condition.

"File not in graphics format" - means that the speacified file is not in
SciPlot graphics format. Check to see if the filename is correct or was
produced by a current version of SciPlot.

"Graphics file too large for memory" - means that the graphics file
specified cannot be processed by VEACTOR due to inadequate memory sort
space.

"Too many vectors for memory" - means that number of vectors per
processing window is too dense. Try using the VECTOR.LRG object deck to
generate the VECTOR.EXE command file.


The VECTOR program supports IBM Graphics, IBM ProPrinters, EPSON MX-80,
FX-80 with GRAFTRAXPLUS, FX-85, FX-850, LQ-800 dot matrix printers
connected on an 8-bit parallel I/O interface.  All 8 bits are necessary
to register the full resolution of the graphics printers.  The resolution
obtained is a plot frame of (960,1920,2880) pixels over 8 inches in the
horizontal direction by (1800,2160) pixels over 10 inches in the vertical
direction. The feature of positioning (1/216th, 1/180th) of an inch is
used, giving a basic resolution of (120,240,360) by (180,216) pixels per
inch over a unit square of one inch on a side.  The IBM
Graphics/ProPrinter, and the EPSON FX-80,85,850 printers have twice the

                                                                      80
resolution as that of the EPSON MX-80.  The hardware requires double
passes to absolutely register two dots in adjacent columns for this high
resolution mode.  This is the reason for the lengthy processing time in
this mode.

There is no paper positioning done by VECTOR. Therefore, the user must
position the paper before executing the VECTOR program.  This is done
purposefully to allow plots to be manually positioned.  It is possible to
imbed plots in full text with a careful alignment of the paper.

The HP Pen Plotter, the HP LaserJet, and the Apple LaserWriter are all
supported by VEACTOR to register the graphics files produced by SciPlot.


 19. 6 OzMap Example
       -------------

You can prepare and print a series of maps as follows:

You start by displaying a map with OzGIS and adding any text etc. When it is
ready you save the map. There are two options for saved displays; either can be
used but when saved for hardcopy output the screen is not saved so takes less
disk space.

The OzMap program is then started.

The name of the saved map file is given and a HARDCOPY! device file chosen.
Use the default one initially.

Select "Display map" from the files menu.

Now select CHANGE DISPLAY DEVICE

choose the printer metafile via PRINTER METAFILE (for VECTOR program)

Use "Display Map" to output the map to the file; give the file name e.g. phred.

Quit.

Type VECTOR to execute the program.

Accept all default values (dot matrix printers) and give the Graphics file as
phred.hrd (note the file extension).

The map will be printed.

 19. 7 Fitting Maps on the Page
       ------------------------

If you find that maps printed on-line are not appearing neatly on the
page you should output maps as meta-files and use the VECTOR program
to print / plot them.

The developers, MicroGlyph Systems, have supplied the following:

     The Apple LaserWriter and the HP Pen Plotters (7440, 7470,7475,7550) all
require special attention. In order to  register a plot frame correctly, it is
necessary to use proper offsets and axes dimensions. The Apple LaserWriter must

                                                                      81
have at least a .25 inch left margin and a .5 inch bottom margin reserved. The H
Pen Plotters all have different basic plot  frame parameters.

     Two tables have been prepared which will allow the user to have a portrait
layout or a landscape layout for plot frames. The ANGLE and XTRANS/YTRANS
arguments will be used from these two tables to obtain the  desired layout for
plotting. The x-axis and y-axis lengths from  the tables serve as limits to the
plot area. The DEMO.FOR program  reflects the use of the PORTRAIT layout
parameters from the tables. If VECTOR is used to register a graphics file (which
has been  produced by using VECDEV=10) for any device other than an EPSON  dot
matrix printer, then the correct layout parameters for that  destination device
must be used to guarantee correct registration.  The following tables contain
the correct parameters for Portrait  or Landscape layouts:



                    Portrait Layout Parameters


 -------------------------------------------------------------------
| Device   Device      Paper  ANGLE X-Axis   Y-Axis XTRANS  YTRANS  |
| Code     Type        Size   Degs  Length   Length Offset  Offset  |
 -------------------------------------------------------------------
    10     Epson,HPLJ 8.5x11   0.0   8.0     10.0     0.0     0.0
    11,20  Apple LW   8.5x11   0.0   8.0     10.0     0.25    0.50
    12     EPS File   8.5x11   0.0   8.0     10.0     0.0     0.0
    13,21  HP-7470A    US/A   90.0   7.497   10.094  10.094   0.0
    13,21  HP-7470A   MET/A4  90.0   7.497   10.682  10.682   0.0
    13,21  HP-7475A    US/A   90.0   7.803   10.158  10.158   0.0
    13,21  HP-7475A    US/B   90.0  10.158   16.306  16.306   0.0
    13,21  HP-7475A   MET/A4  90.0   7.566   10.818  10.818   0.0
    13,21  HP-7475A   MET/A3  90.0  10.818   15.834  15.834   0.0
    13,21  HP-7550A    US/A   90.0   7.683    9.966   9.966   0.0
    13,21  HP-7550A    US/B   90.0   9.966   16.121  16.121   0.0
    13,21  HP-7550A   MET/A4  90.0   7.447   10.652  10.652   0.0
    13,21  HP-7550A   MET/A3  90.0  10.652   15.649  15.649   0.0
    14     CGM File   8.5x11   0.0   8.0     10.0     0.0     0.0
    15     WPG File   8.5x11   0.0   8.0     10.0     0.0     0.0


                    Landscape Layout Parameters


 -------------------------------------------------------------------
| Device   Device      Paper  ANGLE X-Axis   Y-Axis XTRANS  YTRANS  |
| Code     Type        Size   Degs  Length   Length Offset  Offset  |
 -------------------------------------------------------------------
    10     Epson,HPLJ 8.5x11  90.0   10.0     8.0     8.0     0.0
    11,20  Apple LW   8.5x11  90.0   10.0     8.0     8.25    0.50
    12     EPS File   8.5x11  90.0   10.0     8.0     8.0     0.0
    13,21  HP-7470A    US/A    0.0  10.094    7.497   0.0     0.0
    13,21  HP-7470A   MET/A4   0.0  10.682    7.497   0.0     0.0
    13,21  HP-7475A    US/A    0.0  10.158    7.803   0.0     0.0
    13,21  HP-7475A    US/B    0.0  16.306   10.158   0.0     0.0
    13,21  HP-7475A   MET/A4   0.0  10.818    7.566   0.0     0.0
    13,21  HP-7475A   MET/A3   0.0  15.834   10.818   0.0     0.0
    13,21  HP-7550A    US/A    0.0   9.966    7.683   0.0     0.0
    13,21  HP-7550A    US/B    0.0  16.121    9.966   0.0     0.0

                                                                      82
    13,21  HP-7550A   MET/A4   0.0  10.652    7.447   0.0     0.0
    13,21  HP-7550A   MET/A3   0.0  15.649   10.652   0.0     0.0
    14     CGM File   8.5x11  90.0   10.0     8.0     8.0     0.0
    15     WPG File   8.5x11  90.0   10.0     8.0     8.0     0.0



                                                                      83
                   20. TERRITORY DEFINITION
                       ====================



This chapter describes the facilities that can be used to define
territories in terms of zones (polygons) in some displayed base map.





Usually territories are to be developed from base zones according to some
criterion;  e.g. Sales territories should all have similar sales potential;
e.g. School districts should have similar numbers of children.

The operations are as follows.

     A base map is displayed:  Usually this will be a standard geographic
     file (e.g. Melbourne postcodes).  Basic OzGIS facilities are used
     to subset files if non-standard regions are required.

     Specification of territories:  Each territory has a unique 10
     character name.  Zones are assigned off the screen with the cursor.
     Zones can be moved between territories and deleted.  Territories can
     be defined or deleted at any time.

     Specification of a base-map attribute file:  Territory attributes are
     continually calculated by adding the values for the base zones in each
     territory.  The derived values are quantised (usually sequential
     colour 121 class method), the territories coloured, and a legend and
     histogram of sorted values displayed. There can be no missing data.

     Zones can be shuffled according to the displayed territories attribute
     values to meet the assignment criteria  while watching the legend
     and histogram.

     When territory assignment is complete, the definition is output as a
     combine file.

First choose the New pulldown menu:

START NEW SET OF TERRITORIES INTERACTIVELY
START NEW SET OF TERRITORIES FROM COMBINE FILE

This gives the choice of starting a new set of territories by selecting
regions with the box-cursor, or reading in a pre-defined set of territories off
a combine file that is probably the result of a previous run of OzTerr.

The Define menu is used to specify the zones in each territory

DISPLAY TERRITORY NAMES
DEFINE NEW TERRITORY
DELETE A TERRITORY
ADD ZONES SELECTED WITH BOX-CURSOR TO A TERRITORY
ADD A ZONE SELECTED WITH CURSOR TO A TERRITORY
DELETE ZONES SELECTED WITH BOX-CURSOR FROM A TERRITORY

                                                                      84
DELETE A ZONE SELECTED WITH CURSOR FROM A TERRITORY
CHANGE BASE ZONE ATTRIBUTES
CHANGE THE QUANTISATION METHOD
OVERLAY MARKERS FOR SITES IN GEOGRAPHIC FILE
OVERLAY NAMES FOR SITES IN GEOGRAPHIC FILE
OVERLAY LINE SEGMENTS FROM A GEOGRAPHIC FILE
OUTPUT TERRITORY NAMES AS GEOGRAPHIC FILE
OUTPUT TERRITORIES AS COMBINE FILE

Select "Display map" from the files menu.

You define territories using the options:

DISPLAY TERRITORY NAMES
DEFINE NEW TERRITORY
DELETE A TERRITORY


Usually you are trying to balance territories e.g. you may display an
attribute that is number of customers and the try to give each salesman
a territory with about the same number of customers. To  do this you
define the correct number of territories making a guess at their size
and then shuffle the zones between the territories while monitoring
the results by using "Display Map" to display the map. The options relevant to
modifying territories are:

ADD ZONES SELECTED WITH BOX-CURSOR TO A TERRITORY
ADD A ZONE SELECTED WITH CURSOR TO A TERRITORY
DELETE ZONES SELECTED WITH BOX-CURSOR FROM A TERRITORY
DELETE A ZONE SELECTED WITH CURSOR FROM A TERRITORY

You can add overlays to the displayed map to provide "navigation" with:

OVERLAY MARKERS FOR SITES IN GEOGRAPHIC FILE
OVERLAY NAMES FOR SITES IN GEOGRAPHIC FILE
OVERLAY LINE SEGMENTS FROM A GEOGRAPHIC FILE


Finally the territory definitions can be output to a combine file that can be
used to amalgamate the base zones and related attributes (see data preparation)
to get a geographic and attribute file for mapping by using the option OUTPUT
TERRITORIES AS COMBINE FILE.

You should have line segments data for amalgamation. If you started with
polygon data, the polygons will simply be renamed during the amalgamation
process.


You can also output a points geographic file that can be used as an overlay
to label the territories on a map by using
OUTPUT TERRITORY NAMES AS GEOGRAPHIC FILE.


                                                                      85
                   21. ADDRESS MATCHING / GEOCODING
                       ============================




Address matching enables location data to be mapped where the locations are
specified as addresses.

The address matching software is under development. The first version is
available in this release.




 21. 1 Introduction
       ------------

Many organisations have data which are spatially referenced by addresses, such
as customer databases.

These data can be shown on a zones map by accumulating the data within each
postal district and displaying the results using digitised postal district
boundaries. Examples are total number of customers and average sales amount.

Digital data are now becoming available that contain address information e.g.
the US Census TIGER data. These data enable the locations of the attribute data
to be extracted as points and maps produced with or without related attribute
data.

The OzGIS system allows digitised road data and their associated addresses to
be processed. Sets of addresses can be processed to produce geographic files of
point locations. These point files can then be displayed in the usual ways,
either as symbols or names as map overlays or as sites sized according to
some attribute data.

For example, a bank may want to extract points using the addresses of
some customers and then map the average monthly account balances.

 21. 2 Addresses
       ---------

An address is made up of three parts, a number, a name and a postal code.
Examples are:

123 Main Street 654321
Hyde Park
12 Funny Farm Drive, Hicksville 2601

1. The number is a simple integer. Common variations such as 22A, 5-6, 5/66 etc
are not supported. If a number is not given the point will be placed in the
centre of the geographic feature.

2. The name must be given, and is the main part of the address for matching.

3. The postal district is an integer number that helps processing in cases
where the same address name is used in different districts. It need not be

                                                                      86
given.


 21. 3 Data entry
       ----------

Lines data can be entered with the normal process. Addresses are supported for
TIGER data and data in standard form. Other formats will be supported according
to availability of data and demand.

Only line data is supported as that is what is currently available. Typically
the data will be roads.

Two ranges of street numbers will usually be associated with a road, a set of
odd numbers down one side and even numbers down the other e.g. a digitised line
segment may have road name "Hollywood Boulevarde" and number ranges 111 to 179
and 120 to 220.

A road may also have one range (e.g. 1 to 200) or no range may be given.

The order of the road numbers defines the direction of the road. The direction
does not have to be the same for the odd and even numbers. If two ranges are
given and one is not odd and the other even, a single range is derived from the
limits, but the direction must be the same as defined by the two ranges.


 21. 4 Address Matching
       ----------------

An option is provided in the data preparation process to match addresses in a
data file with those in the digitised line data in a geographic file.

The major difficulty is the matching of the road names allowing for differences
in spelling.

After a match is found, the number in the given address is used to find the
distance along the road (using the ranges) and hence a location is calculated.

The set of addresses are given on a data file that has the following:

1. An identifier that can be used to attach attribute data to the point and
which can be used as a label on maps. If no identifier is given the road name
will be used. This identifier would often be a database primary key.

2. The road number. If not given the generated point will be the centre of the
road.

3. The road name. Mandatory.

4. The post (zip) code. Optional.

A geographic file of points is generated. Any addresses that cannot be matched
are listed on the OZGIS.OUT file.


                                                                      87

 21. 5 Matching Addresses
       ------------------


Matching takes place on upper case characters i.e. case is not significant e.g.
"Main St" and MAIN st" match.

Multiple blanks are removed e.g. "Grand Parade" matches "Grand      Parade".

A parameter file is used to convert parts of the names. This is commonly used
to handle abbreviations e.g. ROAD and RD.

Matching is controlled by a level:

Level 1. Every character in the names in the geographic and data files must be
the same e.g. "PHREDS ROAD" and PHRED ROAD" are not the same.

Level 2. Every character of the shorter name must match the other e.g. "phred"
would match the above two strings.

Level 3. The first word in each name must match e.g.  "Bloggs Street" and
"Bloggs Ave" match.

Level 4. Matching is carried out by using derived names e.g. vowels are all
treated the same, repeated letters are removed, non alphabetic characters are
all the same.

Level 5. Matching uses the "soundex" algorithm



 21. 6 Procedure
       ---------

Address matching is an option in the data preparation process.

Select PREPARE DATA FOR DISPLAY from the top menu, which gives the menu:

TUTORIALS & SYSTEM INFORMATION
PROCESS GEOGRAPHIC FILES
PROCESS ATTRIBUTES FILES
PROCESS NAMES FILES
OUTPUT EXTERNAL DATA FILES
ADDRESS MATCHING
CHANGE DEVICE FILE

So you choose ADDRESS MATCHING, which displays the menu:

EXACT MATCHING FOR POINTS OVERLAYS
MATCH FOR START OF ADDRESS FOR POINTS OVERLAYS
MATCH FOR FIRST WORD OF ADDRESS FOR POINTS OVERLAYS
DESPERATION MATCHING FOR POINTS OVERLAYS
EXACT MATCHING FOR SITE MAPPING
MATCH FOR START OF ADDRESS FOR SITES MAPPING
MATCH FOR FIRST WORD OF ADDRESS FOR SITES MAPPING
DESPERATION MATCHING FOR SITES MAPPING

                                                                      88

These options correspond to the 4 matching levels for either point overlays
or site mapping.

You have to specify a number of files:

1. the geographic file that contains the roads and the road names and address
limits

2. Your data file containing the addresses to be matched

3. A parameter file of abbreviations to help the matching process e.g. AVE is
defined as the abbreviation for Avenue

4. the name of the geographic file to be generated with the points location

After you have generated the points geographic file you should check the
file OZGIS.OUT to see how well the addresses were matched. You may then want
to change some of the addresses in the data file to improve the hit rate.

You can now map the data with the OzGIS program. This is covered in other
chapters, but briefly:

DISPLAY GEOGRAPHIC FILES (NO ATTRIBUTES) is used to display the points as
symbols.

You would probably then use DEFINE GEOGRAPHIC OVERLAYS and add your roads file
as a lines overlay and also overlay the names of the points.

DISPLAY SITES FOR AN ATTRIBUTE FILE would be used if you have attribute data
for the points. You would probably add the roads as a lines overlay and the
identifiers as a names overlay.

DISPLAY ZONES AND SITES FOR TWO ATTRIBUTE FILES could also be used if you
want to display other data such as Census data as a zones map underneath
the points with their attribute data.

The points could of course be added as overlays to any map.

 21. 7 Data
       ----

You specify the addresses you want to match in a data files with fixed format
records:

10 bytes  Identifier. If blank the road name is used (first 10 bytes)

50 bytes  Address

For example, the demonstration file DEMOMTCH.DAT looks like:

EXAMPLE ADDRESSES FOR MATCHING - DEMOMTCH.DAT
ADDRESS001         1 GReat north road 2600
                 666 GReat north road 2600
JOE BLOGGS       333 GReat north road 2600
ADDRESS004               GReat north road 2600
            333 GReat north road
PIZZA KING      GReat north road

                                                                      89
ADDRESS007  333 GReat              2600
HARRY S     333 GReat north rd     2600
ADDRESS009  333 GReet narth read   2600
ADDRESS011  666 GReat    north     road   2600
ADDRESS012  666 Molonglo Gorge     2600
ADDRESS013               Molonglo Gorge
                  11 Northbourne Ave 2602
ADDRESS015 44 Northbourne Ave    2600
ADDRESS016 10 Northbourne Ave    2600
ADDRESS017 68 Northbourne Ave    2600
ADDRESS018 57 Northbourne Ave    2600
ADDRESS01940 EPPING HWY
ADDRESS020 33 EPPING HWY


 21. 8 Abbreviations parameter file
       ----------------------------

A parameter file must be given to allow for abbreviations such as ST, AVE, RD

A sample file from the USA Census TIGER documentaion is provided \OZGIS\USA.PRM

You should set up your own abbreviation file. The shorter it is, the faster will
be the matching process.

The first record of the file is a comment, and each following record is:

30 bytes text
10 bytes  abbreviation


The file must be in upper case, and the abbreviation must be shorter than the
text string.

The demonstration file is DEMOMTCH.PRM:

Address matching parameter file DEMOMTCH.PRM
AVENUE                        AVE
BOULEVARD                     BLVD
CIRCLE                        CIR
DRIVE                         DR
FREEWAY                       FWY
HIGHWAY                       HWY
MOTORWAY                      MTWY
PARKWAY                       PKY
PLACE                         PL
ROAD                          RD
STREET                        ST




 21. 9 Handling Errors
       ---------------

The results of the matching process are written to the log file OZGIS.OUT

Each data record is listed with either "MATCHED", "DUPLICATE" or "REJECTED".

                                                                      90
When the names match both the data and geographic file  addresses are listed as
well as the level of the match.

The output will be of the form:


 ======= ADDRESS MATCHING AT LEVEL 4 ======


GEOGRAPHIC FILE demoaddr
ADDRESSES  FILE demomtch
PARAMETER  FILE demomtch

MATCHED          333     GReat north road   2600
MATCHED          666     GReat    north     road             2600
NO MATCH         666     Molonglo Gorge     2600
NO MATCH          68     Northbourne Ave    2600
MATCHED           11      EPPING HWY                            0
MATCHED           33            EPPING HWY                      0
NO MATCH          33     EPXXING HWY                            0


                                                                      91
                   22. SPATIAL OPERATIONS
                       ==================




This chapter describes the facilities that enable a new geographic
file to be generated that is the result of spatial operations such as union
and intersection between the spatial objects in two input geographic files.

The options have not been fully tested.




 22. 1 Operations
       ----------


The operations take place between the objects in two input geographic files,
with the resultant objects being output to a new geographic file.

The following operations are supported:

. Intersection of points with polygons

  For example, extract all sightings (points) of the wedgetail eagle within
  vegetation type 100 (polygons)

  For example extract all retail sites within competitor's store catchments
  (polygons).

  This is a point-in-polygon operation i.e. the points in one file that lie
  inside any of the polygons in the second file are selected.

. Intersection of lines with polygons

  For example, select all roads that are within the franchise area. (then match
  addresses)

  This is a crossing operation i.e. the parts of any lines that cross (are
  inside of) the polygons in the other file are output.

. Intersection of polygons with polygons

  For example, Extract polygons that have soil types (feature codes) 500 to 600
  and forest trees feature codes 77 to 88

  For example, Extract Census districts within the digitised areas covered by
  all hospitals.

  The polygons that are the overlapped parts of any pairs of polygons from
  the two files are output (an AND operation)

. Union of polygons with polygons.

  For example, Extract polygons that have soil types  500 to 600  or

                                                                      92
  forest trees feature codes 77 to 88

  Pairs of polygons from the two input files that overlap are merged to
  form new polygons. Those that do not overlay are output as is.

. Buffer generation

  Generation of buffers at a given distance around spatial objects may be
supported in future releases.




Two levels of polygons will be supported:

1. Simple polygons

Single polygons are processed. There is no regard for polygons inside other
polygons. Polygons with the names OUTSIDE or INSIDE are ignored.

This will often be all that is required.

These data can have been entered into the system as one
of the polygonal formats supported (SAS, Atlas etc).

2. Complex polygons NOT IMPLEMENTED YET

This handles zones which are made up of any mixture of polygons, some of
which can be inside others to a considerable depth.


The results of the polygon processing is a file of line segments that can be
built into polygons with the zone/polygon building process.


 22. 2 Feature codes
       -------------

Processing can take place for a range of feature codes or the whole of the
files can be processed.

A new feature code must be specified for the generated objects. Optionally the
existing feature codes for both files of objects can be added as well.


 22. 3 Procedure
       ---------

When the SPATIAL OPERATIONS item is selected from the top menu the following
menu appears:

INTERSECT POINTS (SECONDARY) WITH SIMPLE POLYGONS (PRIMARY)
INTERSECT LINES (SECONDARY) WITH SIMPLE POLYGONS (PRIMARY)
INTERSECT SIMPLE POLYGONS  WITH SIMPLE POLYGONS
UNION OF SIMPLE POLYGONS  WITH SIMPLE POLYGONS
INTERSECT POINTS  WITH SIMPLE POLYGONS FOR FEATURE CODES
INTERSECT LINES  WITH SIMPLE POLYGONS FOR FEATURE CODES
INTERSECT POLYGONS  WITH SIMPLE POLYGONS FOR FEATURE CODES

                                                                      93
UNION OF POLYGONS  WITH SIMPLE POLYGONS FOR FEATURE CODES

You select the appropriate option. You can either process all the geographic
data or subset it for a feature code range.

Then you have to give the names of the two input geographic files. As indicated
by the menu items, the primary geographic file is always a file of polygons
while the secodary geographic file is the points or line segments or polygons.

You also have to give a name for the geographic file that will be generated.

You always have to provide a feature code (a positive number) for the
generated objects, and can optionally have the feature codes from the
intersected (or unioned) pairs of objects included in the new objects.

Polygons are not directly generated. If you intersect or form the union of
polygons with polygons the output is line segments which then have to be
built into polygons with the zone/polygon building process.



                                                                      94
                   23. SITE LOCATION / ALLOCATION
                       ==========================



Algorithms are provided to aid in site selection for applications such as
the siting of new schools, shopping centres or fast-food outlets.

The facilities are based on ILACS (Interactive Location Allocation in
Continuous Space) by Mike Goodchild.

Available for WINDOWS, not for DOS.



 23. 1 Introduction
       ------------


The selection of a site for some service has two parts:

1. Location of the site.

2. Allocation of the data points to the site.

The data are a set of point locations and attribute data giving the "demand" at
each point.


 23. 2 Example
       -------


Suppose there are three breweries in Australia and you want to know a good
place to build another one.

Select "Location Allocation" from the "Applications" menu.

Give the geographic file name as OZ and the attribute file as OZ.

Choose an appropriate attribute - obviously "Beer consumption"

Give a name for the generated geographic file, say BREWERY

A solution will be displayed.

Now select "Give site a name" from the "Sites" menu and give the fourth site the
name NEW BREWERY

Now for each of the existing sites (SITE001 to SITE003) choose "Digitise fixed
location for a site" and choose a location with the mouse.

You have now specified the locations of the three existing breweries and fixed
them at those locations. The new brewery site is still mobile.

Finally use one of the algorithms from the "Algorithm" menu to generate a
solution.

                                                                      95


 23. 3 Solutions
       ---------


There can be up to 5 current solutions, referred to by number. Each provides
storage for a complete solution, giving the locations, optional capacities and
mobilities of each of the sites

There is always a current solution (initially number one).

The contents of each solution are intially zero, so each site is located at
(0,0) with zero capacity and is free to move.

The Alternating and Tornqvist algoriths take the contents of the current
solution and place the generated optimum solution into a new, specified current
solution.


 23. 4 Sites
       -----


The storage available for the mattrix of site/demand points is limited, and
large numbers of demand points allow smaller numbers of sites to be allocated.

Sites are referred to by name. These are initially SITE001, SITE002 etc, but
they can be renamed.

Sites can be mobile or fixed during optimisation; many situations have existing
fixed sites and are allocating some new facilities. e.g. the schools in a city
may be investigated with the view of keeping most, building a few new ones, and
closing some down.

Site locations can be set to random locations within the map area or to a
random sample of the data points.

The capacities of the sites can be initialised by dividing the total demand
equally among them.

Sites can be located with the cursor / mouse.


 23. 5 Geographic Data
       ---------------


A geographic points file gives a set of locations from which the demand is
considered to come. Typically the points will be thye centroids of Census
polygons. The points are displayed as symbols and any line segments (typically
the boundaries of Census district polygons) will also be displayed.

Points should have unique names, but the case of multiple polygons within
Census districts (and hence the same name) are handled by dividing the
attribute value equally between them.


                                                                      96

 23. 6 Attribute data
       --------------


The attribute file gives the demand at the point locations.

The data are typically demographic data such as Census data.

The data depend on the application and will often be prepared by applying
arithmetic operations to basic attribute data.

In some cases the data are obvious e.g. Census data giving the total population
in the age group 11 to 17 years may be used when siting high schools.

Other cases may be more complicated and models developed by statistical
analysis of other data e.g. an attribute for siting a maternity hospital may be
20% of women aged 17 to 25 years, 25% of women aged 26 to 35 years and 5% of
the number of women aged 36 to 45 years. Sometimes a simple attribute may be
found to correlate well enough to be used as an indicator variable.

The algorithmns work with positive integer values, so arithmetic operations may
have to be used to scale and offset the attribute data. The data values should
have a large range.



 23. 7 Allocation
       ----------


An allocation consists of a matrix of assignments of demand from each point to
each site. Only one allocation is active at any time.

An allocation is defined explicitly by the allocation operation (the point of
Minimum Aggregate Travel using steepest descent) or implicitly by the use of
the Alternating or Tornqvist algorithms.


 23. 8 Parameters
       ----------


A number of parameters are used to control operations. They have default values
and can be changed during a session.

Number of sites - the maximum possible depends on the number of points.

Constrained - initially unconstrained. During allocation, if the constrained
option is in effect the demand allocated to a site may not exceed that sites's
capacity as defined. Constrained allocation invokes a solution to the
transportation problem, while unconstrained allocation is to the nearest site.

Maximum iterations - limits for each algorithm.

Criterion distance - Iterations cease when movement is less than this amount in
coordinate units.

                                                                      97

Steps - In the Tornqvist algorith steps start at the given value, decrease by
the given factor to the given minimum.

KM scale - Used to give reports in Kilometres. The scaling is calculated for
Lat/Long, otherwise it is 1000 (metres assumed). Note that the effect of
latitude is handled approximately.


 23. 9 Barriers and Freeways
       ---------------------


Travel limitations such as rivers can be simulated by specifying straight line
barriers with the mouse / cursor. Barriers can also be used for other
situations such as political boundaries.

Freeways and travel speed ratios can also be specified.


 23.10 Outputs
       -------


The current allocation is continually output to a geographic file and
displayed. The file name can be changed, and the file can be used for other
mapping applications. The file contains:
      The site locations as points
      Lines joining the sites and the allocated points (feature code 1)
      Barriers (featurecode 2)
      Freeways (feature code 3)

A combine file can be generated giving the points allocated to each site.
This can be used to accumulate attribute data for mapping at the sites in the
generated geographic file. It could also be used to amalgamate polygons to form
territories (if there are no repeated points i.e. weights < 1. In this case
you will have to output the combine file as a data file and edit it).

The current allocation can be shown on the screen, and a full report can be
output to the usual OZGIS.OUT file.

The allocation can be saved to (and restored from) a file.



                                                                      98
                   24. SITE CATCHMENTS
                       ===============



Catchments can be defined as contours around sites and the attribute data
extracted from base zones (usually Census data) for mapping.





 24. 1 Introduction
       ------------

A common requirement is to know the demographics of an area surrounding a site.

For example, a shopping centre manager would like to know how many customers of
a particular type should be attracted to the centre.

The basic source of demographic data is usually Census data.  The aim of the
site catchment software is to determine weights to be applied to Census
districts around a site so values can be accumulated.

As it is expected that the attraction to a site will fall away with distance,
the procedure is to define a set of contours around each site.

For example, it may be decided that 95% of people living within 10KM of a
hospital will go there in am emergency, 50% within 20KM outside that, and 10%
within 30KM.

The contours are defined interactively on the screen, and their shape will
reflect other influences such as barriers and competition.


                                                                      99

For example, the contours may be drawn for two sites at locations X and Y as:

                                   *
                                 *    *
                                *       *
                              *           *
                            *              *
                           *                *
                         *         *         *
                       *         *   *        *
                      *        *       *       *
                      *       *   ***   *       *
                      *      *   *   *   *      *
                      *      *  *  X  *  *      *
                       *     *   *   *  *      *
                        *     *   ***  *      *
                         *     *      *      *
                          *     ******      *
                            *              *
                             *          ***
                              *********




               *
             *   *
           *       *
         *   ***   *
        *   *   *   *
        *  *  Y  *  *
       *   *    *   *
        *   * *    *
          *  *    *
           *     *
             **


After the catchment contours have been defined they can be overlayed on the
underlying Census boundaries to find which Census districts lie within each
contour.

The Census districts, the proportion within the contours and the contour levels
are used to produce a list of districts and their weights for each site. The
lists are output as a combine file which can be used to amalgamate Census data
for mapping.

The site names and locations are output as a geographic file that can be used
with the attribute file to map the sites.

Geographic files containing the contour lines and other site definition
graphics can  also be produced for use as an overlay on maps.

                                                                     100

 24. 2 First example
       -------------

Select Applications from the top menu and then Site catchment definition.
The main site catchment menu is:

Files
Define
Assemble
Help


Give the geographic file as CANBL81

Select DEFINE and INCLUDE SITES FROM A CATCHMENT FILE

Give the catchment file as catch

A set of site catchments in Canberra will be displayed.

 24. 3 Data
       ----

You need a geographic zones file, and an attribute file of demographic data
(typically Census data).

The attribute used will relate to the project e.g. to site child-care centres
you may use 0 to 4 year olds.

The base map zones cannot have any missing data.

The following demonstration files are supplied:

L81SEG.DAT is a data file of geographic line segments supplied by AUSLIG.
The zones are Local Government Areas (LGAs).

L81ATTR.DAT is a data file of demographic data
L81.att is the entered attribute data

ACTSUBUR.DAT and ACTSUBUR.GEO are geographic points/names for Canberra suburbs.

CANBL81.GEO is a geographic file of LGAs for canberra. It was prepared by
building polygons from L81SEG and the subsetting the file for the attribute
file son none of the polygons have no data.

CATCH.CAT is and example catchment file defining sone sites in Canberra for the
example files.

 24. 4 Example
       -------

Suppose you want to analyse some shopping centre sites in Canberraand you have
a geographic file of boundaries called CANBL81, a geographic file of
names called ACTSUBUB and a file of Census data for the zones called
CANBL81.
Select Applications from the top menu and then Site catchment definition.

                                                                     101
The main site catchment menu is:

Files
Define
Assemble
Help

First of all the catchments have to be defined, so select Define

The catchments are defined relative to a base map, and there is the concept of
a current set of sites being worked on.

So give the geographic file as CANBL81. The base map is displayed.

The following menu appears:

ADD A NEW SITE
DELETE A SITE
RENAME A SITE
REPOSITION SITE LOCN, NAME OR SYMBOL
MODIFY SITE CONTOURS
SEARCH GEOG FILE FOR SITES INSIDE A CONTOUR
CHANGE DISPLAYED REGION
TEMPORARYILY OVERLAY OTHER CATCHMENT FILE ON BASE MAP
OVERLAY GEOGRAPHIC FILES ON BASE MAP
DISPLAY ALL CURRENT SITES
INCLUDE SITES FROM CATCHMENT FILE
INCLUDE POINTS FROM GEOGRAPHIC FILE
INCLUDE POLYGONS FROM GEOGRAPHIC FILE
DISPLAY TEXT
OUTPUT TO CATCHMENT FILE
OUTPUT TO CATCHMENT FILE AND EXIT

Next display the suburb names by selecting OVERLAY GEOGRAPHIC FILES and then
OVERLAY SITE NAMES FROM A GEOGRAPHIC FILE. Give the file name as ACTSUBUR
The names are to help "navigate" so are not really necessary. You might also
display roads (if you have the data).

You may also want to use the CHANGE DISPLAYED REGION option to change the part
of Canberra that is displayed.

Now a new set of catchments can be defined (you can read in an old set)

Select ADD A NEW SITE, which displays the menu:

ADD NEW SITE, CURSOR POSN
ADD NEW SITE, TYPED POSN

Sites are initially defined as circles. You provide a name, the radius of the
circle, and a weight.

Suppose it has been decided as a starting point the 75% of people living within
a 5KM radius of a shopping centre will buy all their groceries there. So select
ADD NEW SITE, CURSOR POSN for each site
Give a name
Select the location with the cursor
Give the radius as 5.0
Give the weight as 0.75

                                                                     102

You can define several sites and modify them in several ways e.g. add more
contours.

Finally use  OUTPUT TO CATCHMENT FILE to store the site definitions.

Now the first version of the catchments have been defined, the proportions of
the underlying base polygons that are within the contours can be calculated for
each site and the weights applied.

Select GENERATE CATCHMENT FILE ZONES AND WEIGHTS

Give the names of the base zones geographic file as CANBL81T (it could be
something else) and the name of the catchment file (CATCH is the example file)

The polygons and the contours are now intersected to find the areas of the
common parts and the catchment file is updated for the list of zones and
weights for each site.

Now the mapping data has to be output to files for mapping:

Select Assemble, which gives the menu:

INCLUDE SITES FROM CATCHMENT FILE
CHANGE SYMBOL DISPLAY LOCATION
CHANGE NAME DISPLAY LOCATION
CHANGE DISPLAYED REGION
OUTPUT ZONES AND WEIGHTS TO COMBINE FILE
AMALGAMATE ATTRIBUTE DATA FOR COMBINE FILE
OUTPUT GEOGRAPHIC FILE FOR SYMBOLS AND CONTOUR DISPLAY
OUTPUT GEOGRAPHIC FILE FOR SITE NAMES AND OFFSET LINES

First select INCLUDE SITES FROM CATCHMENT FILE and give the catchment files as
CATCH (you could input several files).

Now generate a geographic file for mapping the sites by selecting
OUTPUT GEOGRAPHIC FILE FOR SYMBOLS AND CONTOUR DISPLAY and giving a file name
as say SITES. Then select OUTPUT GEOGRAPHIC FILE FOR SITE NAMES AND OFFSET LINES
and give a file name, say NAMES.

Now accumulate the attribute data for the sites:
First select OUTPUT ZONES AND WEIGHTS TO COMBINE FILE and give the file as
COMB. The combine file will contain the list of zones  for each
site and the weights.

Select AMALGAMATE ATTRIBUTE DATA FOR COMBINE FILE
The attribute file is that for the base zones L81 and the combine file is
COMB. Give the output attributes as SITES.

You can now map the site data, so return to the top menu and select
Map

You now have the two main files for mapping, a points file called SITES and the
related attribute file SITES.

You could now select DISPLAY SITES FOR AN ATTRIBUTE FILE to map the data.

However, you can also display the original base map data at the same time:

                                                                     103

Select DISPLAY ZONES AND SITES FOR TWO ATTRIBUTE FILES

Give the zones attributes file as L81
Give the sites attribute file as SITES
Give the zones geographic file as CANBL81
Give the sites geographic file as SITES

The map is now displayed, with the site symbols on top of the base map.

Now add the contour lines by selecting DEFINE GEOGRAPHIC OVERLAYS and
then OVERLAY LINE SEGMENTS FROM A GEOGRAPHIC FILE. Give the file as SITES.


 24. 5 Geographic files
       ----------------

Sites are intiially defined as circles on the ground of a given size.

The map projection must be known to do this.

The geographic files must be Latitude Longitude with units of degrees.

Census boundary files are usually in this form.

You may have to use the projections options.

In particular, even if the file is lat. long. you may have to write that
information into the file header by:

Select CHOOSE FROM PROJECTION SET 1 and then GEOGRAPHIC LATITUDE LONGITUDE
Then use WRITE PROJECTION DEFINITION INTO GEOGRAPHIC FILE

You will find that the process of intersecting the catchment contours and the
base map polygons is slow. As the speed depends on the number of points in the
polygons and as the process is approximate it is suggested that the data
preparation option be used SIMPLIFY (THIN) LINE SEGMENTS

The catchments are held as latitude / longitude polygons so are independent of
the base map i.e. you can use one base map during definition and another during
the intersection process. The process assumes an even population distribution
across the base map zones, so the smaller the zones the more accurate the
results would be.

Note that the current set of sites being processed must always fit on the base
map.


 24. 6 Catchment files
       ---------------

The system aims to provide facilities for analysis of sites for the
definition of site locations and catchments, the retrieval of data,
development of models and display of results.

The base of the process is the catchment file.
A catchment file holds the definition of several sites.  The sites have
some common grouping (e.g. all part of the same retail chain) and all fit

                                                                     104
on the same base map.

A typical analysis would involve several catchment files, e.g. several sets
of sites each for a different organisations( e.g. several sets, each
defined on different base maps to increase resolution. )

Site definition is carried out for a current set of sites.  These
sites can be modified and new sites defined.  A base map is always
displayed and all the current sites must fit on the displayed map.

Also defined for assistance are any other catchment files relevant to the analys
Site symbols, names and catchments are displayed if they fit on the
map.  These sites cannot be modified.

A catchment file contains the following information for each site.

-    site name (10 characters)
-    site location
-    site symbol display location
-    site name display location
-    catchment contours (up to 5)
-    base zones and weights within catchment

 24. 7 Catchment modification
       ----------------------

The whole process is iterative with catchments being modified and the results
mapped.

The catchment definition menus provide the options (using a displayed base
map):
INCLUDE SITES FROM CATCHMENT FILE
Enables existing sites to be considered.

ADD A NEW SITE
DELETE A SITE
RENAME A SITE
Provides basic site control.

REPOSITION SITE LOCN, NAME OR SYMBOL
Enables shuffling of displayed site information when sites are crowded.

MODIFY SITE CONTOURS
Enables several contours to be defined for a site as circles or digitised
simple polygons. The contours can reflect the interaction between sites and any
barriers.

Contours are essentially simple i.e. they are assumed to be concentric, and do
not cross.

CHANGE DISPLAYED REGION
Enables zooming and panning of the base map.

TEMPORARYILY OVERLAY OTHER CATCHMENT FILE ON BASE MAP
Enables other site catchment files to be added as overlays.

OVERLAY GEOGRAPHIC FILES ON BASE MAP
Enables lines, points etc to be added to the base map.

                                                                     105

INCLUDE POINTS FROM GEOGRAPHIC FILE
Enables a set of sites to be defined as circles (all same radius) at locations
given in the file.


                                                                     106
                   25. DIGITAL CHART OF THE WORLD
                       ==========================


 25. 1 Introduction
       ------------

The Digital Chart of the World (DCW) is a fabulous world-wide database available
on 4 CD-ROMs for the cost of distribution.
Points, lines and text data can be imported in VPF format. Polygons can be built
from the lines with some restrictions.
The data entry process is designed so only the required files are processed.
This means that you do not have to have a CD-ROM drive but can copy the required
files from another PC.

 25. 2 Databases
       ---------

The data comes on four CD-ROMS. Each contains a copy of the world-wide BROWSE
library and one other  library covering a part of the world
BROWSE   all world
EURNASIA Europe and North Asia
SOAMAFR  South America and Africa
NOAMER   North America
SASAUS   South Asia and Australasia

You obviously choose which library you want first.

The BROWSE data base contains data files that cover the whole world, but the
other detailed libraries contain a hierarchy of file directories of data for
5 degree square tiles.

The first process is finding which directories contain the data you require.

 25. 3 Files
       -----

Processing requires two files:
      1. a file that contains the actual data
      2. A feature attribute table file that defines the feature codes of the

Pairs of files are:
Lines  data TXT.  feature xxLINE.LFT
Points data END.  feature xxPOINT.PFT
Text   data TXT.  feature xxTEXT.TFT
Where xx is the main directory

 25. 4 Utilities
       ---------

The DCW files are binary. A VPFDUMP program comes with the data and can be used
for inspection.
A similar program OZDCW is supplied. This can also be used to inspect data
files.
OZDCW must be used to convert the binary DCW files to ascii files in preparation
for data input i.e. the raw DCW files cannot be imported.
Typing OZDCW FILE will list the file

                                                                     107
Hence you often use "OZDCW file | MORE"
To process a file for importing use e.g. "OZDCW file > dataFile"


 25. 5 Coverage directories
       --------------------

The first file to look at is the coverage attribute table at the highest
directory level for the library you want. This is called CAT.

e.g. type "OZDCW BROWSE\CAT. | MORE" to find what is in the BROWSE library

Digital Chart of the World file: \usr\local\DCW\BROWSE\CAT.

191L;
Coverage Attribute Table;-;

**DCWcolumns ====================

ID              =I,  1,N,Row Identifier,-,-,:
COVERAGE_NAME   =T,  8,P,Coverage name,-,-,:
DESCRIPTION     =T, 50,N,Coverage description,-,-,:
LEVEL           =I,  1,N,Topology level,-,-,:;

**DCWdata ===========================

**DCWrow --------------------
1
CO
ONC Compilation Date
3
**DCWrow --------------------
2
DV
Data Volume
3
**DCWrow --------------------
3
DN
Drainage
3
**DCWrow --------------------
4
GR
Geographic Regions
3
**DCWrow --------------------
5
DA
Hypsographic Data Availability
3
**DCWrow --------------------
6
IN
ONC Index
3
**DCWrow --------------------
7

                                                                     108
PO
Political\Oceans
3
**DCWrow --------------------
8
PP
Populated Places
0

Hence Rivers etc are in the drainage coverage, Country boundaries in the
political directory PO etc


 25. 6 Directory Contents
       ------------------

Suppose you want to find out the actual data available in the political
coverage i.e. the PO directory.

type "OZDCW PO\INT.VDT | MORE"


Digital Chart of the World file: PO\INT.VDT

252L;
Political\Oceans Integer Value Description Table;-;

**DCWcolumns ====================

ID              =I,  1,N,Row Identifier,-,-,:
TABLE           =T, 12,P,Name of Feature Table,-,-,:
ATTRIBUTE       =T, 16,P,Attribute Name,-,-,:
VALUE           =I,  1,P,Attribute Value,-,-,:
DESCRIPTION     =T, 50,N,Attribute Value Description,-,-,:;

**DCWdata ===========================

**DCWrow --------------------
1
POAREA.AFT
POPYTYPE
1
Land areas
**DCWrow --------------------
2
POAREA.AFT
POPYTYPE
2
Ocean areas
**DCWrow --------------------
3
POLINE.LFT
POLNTYPE
1
International Boundary
**DCWrow --------------------
4
POLINE.LFT

                                                                     109
POLNTYPE
2
Coastline
**DCWrow --------------------
5
POTEXT.TFT
LEVEL
1
Land place names
**DCWrow --------------------
6
POTEXT.TFT
LEVEL
2
Ocean place names
**DCWrow --------------------
7
POTEXT.TFT
LEVEL
3
Ice Status
**DCWrow --------------------
8
POTEXT.TFT
LEVEL
4
Land place names (diacritical)
**DCWrow --------------------
9
POTEXT.TFT
LEVEL
5
Ocean Place names (diacritical)
**DCWrow --------------------
10
POTEXT.TFT
LEVEL
6
Mountain names
**DCWrow --------------------
11
POTEXT.TFT
LEVEL
7
Mountain names (diacritical)
**DCWrow --------------------
12
POTEXT.TFT
LEVEL
8
Island names
**DCWrow --------------------
13
POTEXT.TFT
LEVEL
9
Island names (diacritical)
**DCWrow --------------------

                                                                     110
14
POTEXT.TFT
LEVEL
10
Desert names
**DCWrow --------------------
15
POTEXT.TFT
LEVEL
11
Desert names (diacritical)
**DCWrow --------------------
16
POTEXT.TFT
SYMBOL
1
Black annotation
**DCWrow --------------------
17
POTEXT.TFT
SYMBOL
4
Blue annotation


Each entry tells you what it is, the attribute feature table you have to use,
and the feature code e.g. the entry:

**DCWrow --------------------
4
POLINE.LFT
POLNTYPE
2
Coastline

Tells you that to to extract the Coast outline you need feature code 2


 25. 7 Example - World Countries
       -------------------------


To map the whole world use the BROWSE library.

First look at the coverage attribute table, which basically tells what
is in the various directories for the library:

Type "VPFdump  \usr\local\DCW\BROWSE\CAT. | MORE"


191L;
Coverage Attribute Table;-;
ID              =I,  1,N,Row Identifier,-,-,:
COVERAGE_NAME   =T,  8,P,Coverage name,-,-,:
DESCRIPTION     =T, 50,N,Coverage description,-,-,:
LEVEL           =I,  1,N,Topology level,-,-,:;
1       CO              ONC Compilation Date
3

                                                                     111
2       DV              Data Volume
3
3       DN              Drainage
3
4       GR              Geographic Regions
3
5       DA              Hypsographic Data Availability
3
6       IN              ONC Index
3
7       PO              Political\Oceans
3
8       PP              Populated Places
0

So rivers will be in the DN directory, towns in the PP directory etc.

In this example look at to PO directory...


As before, start by looking at the Integer Value Description table:

type "VPFdump \usr\local\DCW\BROWSE\PO\INT.VDT : MORE"


252L;
Political\Oceans Integer Value Description Table;-;
ID              =I,  1,N,Row Identifier,-,-,:
TABLE           =T, 12,P,Name of Feature Table,-,-,:
ATTRIBUTE       =T, 16,P,Attribute Name,-,-,:
VALUE           =I,  1,P,Attribute Value,-,-,:
DESCRIPTION     =T, 50,N,Attribute Value Description,-,-,:;
1       POAREA.AFT      POPYTYPE                1       Land areas

2       POAREA.AFT      POPYTYPE                2       Ocean areas

3       POLINE.LFT      POLNTYPE                1       International Boundary

4       POLINE.LFT      POLNTYPE                2       Coastline

5       POTEXT.TFT      LEVEL                   1       Land place names

6       POTEXT.TFT      LEVEL                   2       Ocean place names

7       POTEXT.TFT      LEVEL                   3       Ice Status

8       POTEXT.TFT      LEVEL                   4       Land place names (diacri
tical)
9       POTEXT.TFT      LEVEL                   5       Ocean Place names (diacr
itical)
10      POTEXT.TFT      LEVEL                   6       Mountain names

11      POTEXT.TFT      LEVEL                   7       Mountain names (diacriti
cal)
12      POTEXT.TFT      LEVEL                   8       Island names

13      POTEXT.TFT      LEVEL                   9       Island names (diacritica
l)

                                                                     112
14      POTEXT.TFT      LEVEL                   10      Desert names

15      POTEXT.TFT      LEVEL                   11      Desert names (diacritica
l)
16      POTEXT.TFT      SYMBOL                  1       Black annotation

17      POTEXT.TFT      SYMBOL                  4       Blue annotation

The major interest is the coast and country boundary lines, given by
line feature table POLINE.LFT with the feature column POLNTYPE having
values 1=International Boundary or 2=Coastline

We will also extract the major place names, feature code 1.


You need pairs of files; the data goes into a .DAT file and the attribute table
file into an OzGIS parameter file:

First the lines:

OZDCW PO\POLINE.LFT > \mapping\DCWLINE.PRM (where mapping is the directory, say)
OZDCW PO\EDG.       > \mapping\DCWLINE.DAT

and the text\points data:
OZDCW PO\POTEXT.TFT > \mapping\DCWTEXT.PRM
OZDCW PO\TXT.       > \mapping\DCWTEXT.DAT

Now run OzGIS and import geographic data for two files DCWLINE and DCWTEXT You
select the type of DCWdata being imported and specify the feature codes
required.

Then map geographic data. Display DCWLINE lines for feature code 2 (the coast).
Then overlay lines for feature code 1 (the internal country boundaries, and
overlay DCWTEXT as names at points.


 25. 8 Tiles Example
       -------------

The detailed libraries contain the data in 5 degree square tiles. Each tile is
in a lower level directory. To be inconsistent, the feature table files are
still in the top level directories.

Suppose we want to map the Mergui Peninsular area, Latitude about 12N, longitude
about 98E.

The first thing you have to do is find which directory contains the data

The Face bounding rectangle table tells the extent of each tile


Type "VPFdump \usr\local\DCW\SASAUS\TILEREF\FBR. | MORE"

239L;
"FBR: Face Bounding Rectangle Table";-;
ID              =I,  1,P,Row ID,-,-,:
XMIN            =F,  1,N,Minimum X Coordinate,-,-,:
YMIN            =F,  1,N,Minimum Y Coordinate,-,-,:

                                                                     113
XMAX            =F,  1,N,Maximum X Coordinate,-,-,:
YMAX            =F,  1,N,Maximum Y Coordinate,-,-,:;
1    -180.000092    -55.000000    180.000000    55.000000
2    45.000008    50.000000    50.000000    55.000000
3    50.000008    50.000000    55.000000    55.000000
4    55.000008    50.000000    60.000000    55.000000
5    60.000008    50.000000    65.000000    55.000000
6    65.000015    50.000000    70.000000    55.000000
7    70.000015    50.000000    75.000000    55.000000
8    75.000015    50.000000    80.000000    55.000000
9    80.000015    50.000000    85.000000    55.000000
10    85.000015    50.000000    90.000000    55.000000
11    -180.000092    45.000000    -175.000000    50.000000
12    25.000004    45.000000    30.000000    50.000000
13    30.000004    45.000000    35.000000    50.000000
14    35.000008    45.000000    40.000000    50.000000
....
229    75.000015    10.000000    80.000000    15.000000
230    80.000015    10.000000    85.000000    15.000000
231    85.000015    10.000000    90.000000    15.000000
232    90.000015    10.000000    95.000000    15.000000
233    95.000015    10.000000    100.000000    15.000000 <<<<<<<<<<<<<
234    100.000015    10.000000    105.000000    15.000000
235    105.000015    10.000000    110.000000    15.000000
236    110.000015    10.000000    115.000000    15.000000
237    115.000015    10.000000    120.000000    15.000000
...

So you need tile number 233.  The tile reference attribute table gives
the directory.

Type "VPFdump \usr\local\share\DCW\SASAUS\TILEREF\TILEREF.AFT | more"
94L;
Tile Reference Areas;-;
ID              =I,  1,P,Row Identifier,-,-,:
TILE_NAME       =T,  6,N,Tile Name,-,-,:;
1       \\
2       R\K\12
3       R\K\22
4       R\K\32
5       S\K\12
6       S\K\22
7       S\K\32
8       T\K\12
9       T\K\22
10      T\K\32
11      A\K\11
12      P\K\31
13      Q\K\11
14      Q\K\21
15      Q\K\31
16      R\K\11

...
227     S\G\23
228     S\G\33
229     T\G\13
230     T\G\23

                                                                     114
231     T\G\33
232     U\G\13
233     U\G\23   <<<<<<<<<<<<<<<<<< coast
234     U\G\33
235     V\G\13
236     V\G\23
237     V\G\33
238     W\G\13
239     W\G\23
...

So the data are in sub-directory U\G\23


So to extract the required data from the PO (political) coverage you could:

OZDCW PO\POTEXT.TFT    > \mapping\DCWTEXT.PRM for text
OZDCW PO\U\G\23\TXT.   > \mapping\DCWTEXT.DAT

OZDCW PO\POLINE.LFT    > \mapping\DCWLINE.PRM for line data
OZDCW PO\U\G\23\EDG.   > \mapping\DCWLINE.DAT

OZDCW PO\POPOINT.PFT   > \mapping\DCWPOINT.PRM for point data
OZDCW PO\U\G\23\END.   > \mapping\DCWPOINT.DAT

Note that the feature table files can be large. If you are short of disk space
you need only extract the part of the file that has the IDs covering those of
the data file. For example, if you extract data by say:
OZDCW PO\U\G\23\END.   > \mapping\DCWPOINT.DAT

Then the OZDCW program will print out the number of records. If you look at the
start of the data file by:
MORE < \mapping\DCWPOINT.DAT
the you can find the ID of the first record.

Suppose the first ID is 1234 and there are 100 records, then you can extract
just the required feature data by:
OZDCW -f 1234 -l 1334 PO\POPOINT.PFT   > \mapping\DCWPOINT.PRM

The first and last record IDs have to cover the range of the data.
e.g. OZDCW -f 1000 -l 1500 PO\POPOINT.PFT   > \mapping\DCWPOINT.PRM




As before you find the feature codes by looking at the INT.VDT file


Type " VPFdump \usr\local\DCW\SASAUS\PO\INT.VDT | more"

279L;
Political\Oceans Integer Value Description Table;-;
ID              =I,  1,N,Row Identifier,-,-,:
TABLE           =T, 12,P,Name of Feature Table,-,-,:
ATTRIBUTE       =T, 16,P,Attribute Name,-,-,:
VALUE           =I,  1,P,Attribute Value,-,-,:
DESCRIPTION     =T, 50,N,Attribute Value Description,-,-,:;
1       POAREA.AFT      POPYTYPE                1       Land

                                                                     115

2       POAREA.AFT      POPYTYPE                2       Open ocean

3       POAREA.AFT      POPYTYPE                3       Polar Ice

4       POAREA.AFT      POPYTYPE                4       Pack Ice

5       POAREA.AFT      POPYTYPE                5       Shelf Ice

6       POLINE.LFT      POLNTYPE                1       International boundary,
Dejure
7       POLINE.LFT      POLNTYPE                2       International boundary,
Defacto
8       POLINE.LFT      POLNTYPE                3       International boundary,
Dejure and Defacto
9       POLINE.LFT      POLNTYPE                4       Administrative boundary,
 primary
10      POLINE.LFT      POLNTYPE                5       Administrative boundary,
 major
11      POLINE.LFT      POLNTYPE                6       Treaty or occupancy line

12      POLINE.LFT      POLNTYPE                7       Coastal Closure Line

13      POLINE.LFT      POLNTYPE                8       Ocean demarcation Line

14      POLINE.LFT      POLNTYPE                9       Ice line

15      POLINE.LFT      POLNTYPE                10      Coastline

16      POLINE.LFT      POLNTYPE                11      Ice\Water line

17      POLINE.LFT      POLNTYPE                12      Seawall

18      POLINE.LFT      POLNTYPE                13      International Date Line

19      POLINE.LFT      POLNTYPE                88      Connector

20      POLINE.LFT      POLNSTAT                1       Definite

21      POLINE.LFT      POLNSTAT                2       Approximate boundary or
fluctuating coastline
22      POLINE.LFT      POLNSTAT                3       Indefinite boundary or u
nsurveyed coastline
23      POLINE.LFT      POLNSTAT                4       Manmade coastline

24      POLINE.LFT      POLNSTAT                5       Undetermined coastline

25      POLINE.LFT      POLNSTAT                6       Ice cliff (coastline or
ice line)
26      POLINE.LFT      POLNSTAT                7       River, when boundary

27      POLINE.LFT      POLNSTAT                8       Poly closure line

28      POLINE.LFT      POLNSTAT                9       None

29      POPOINT.PFT     POPTTYPE                1       Small island

30      POTEXT.TFT      LEVEL                   1       Land place names

                                                                     116

31      POTEXT.TFT      LEVEL                   2       Ocean place names

32      POTEXT.TFT      LEVEL                   3       Ice Status

33      POTEXT.TFT      LEVEL                   4       Land place names (diacri
tical)
34      POTEXT.TFT      LEVEL                   5       Ocean Place names (diacr
itical)
35      POTEXT.TFT      LEVEL                   6       Mountain names

36      POTEXT.TFT      LEVEL                   7       Mountain names (diacriti
cal)
37      POTEXT.TFT      LEVEL                   8       Island names

38      POTEXT.TFT      LEVEL                   9       Island names (diacritica
l)
39      POTEXT.TFT      LEVEL                   10      Desert names

40      POTEXT.TFT      LEVEL                   11      Desert names (diacritica
l)
41      POTEXT.TFT      SYMBOL                  1       Black annotation

42      POTEXT.TFT      SYMBOL                  4       Blue annotation


 25. 9 Polygons
       --------

You can build polygons from the line data within OzGIS in the usual way.

However, any polygons that are not complete (closed) will be dropped. This means
that polgons around the edge of tiles disappear. In some cases there seems to be
additional data which may help e.g. there is not only Coast lines but also coast
closure lines.

Within the BROWSE library there is a feature code 9 which gives boundary lines
so extract line feature 9 as well as feature 2=coast. You will find that you
then get polgons for the whole rectangle (-180,-90) to (180,90). You should
however be able to edit the output from OZDCW to throw away the type 9 records
that are not required (look for 90.0).


 25.10 Summary
       -------

. select the library (BROWSE, SASAUS etc)

. OZDCW or VPFDUMP the file CAT. to find the directories\coverages

. OZDCW or VPFDUMP the file INT.VDT in the required directories to find the
   feature codes

. if tiled look at \TILEREF\FBR. and \TILEREF\TILEREF.AFT to find the tile
  directory

. generate data and parameter files for importing into OzGIS with the OZDCW
  program

                                                                     117
      TXT. and xxTEXT.TFT for test
      END. and xxPOINT.PFT for points
      EDG. and xxLINE.LFT for lines


 25.11 Other VPF data
       --------------

The procedure should work for other databases.

One restriction is that only numeric feature codes are handled. If you want to
process databases that use text feature values (e.g. the Digital Nautical
Chart) you will have to set up the pairs of files in the usual way, but the
edit the .PRM file to change all to text feature vales to numbers.


                                                                     118
                     A. MAP DATA FORMATS
                       ================



This appendix describes the data formats supported.


You obtain your data on a file in one of the following formats
and use the appropriate option to read that file and create an OzGIS file
that can be used for mapping.





  A. 1 Introduction
      ------------

The OzGIS system was designed to accept data from external sources.

These data may be supplied in standard formats that are supported by the
IMPORT DATA FILES option in the top menu.

If not, data will  have to be reformatted into one of the system formats
before use.

Map objects are identified by 10 character keys e.g. PARIS, NEW YORK, 12345

Where keys are generated within OzGIS they are usually left aligned numbers.

  A. 2 OzGIS data Formats
      ------------------

Every type of file has a standard format within OzGIS.

The data files have been designed with a simple format which can be easily
generated on computer systems.

Most data are held as character files so that they can be generated by
programs with, for example, database system export procedures, formatted
FORTRAN write statements, or by a text editor.  The record lengths are up to
80 bytes long.

Each file starts with a comment record of up to 80 characters, which should
be used to hold a meaningful description of the file.  The OzGIS system
will display this comment when data files are interrogated, so it is in
your interest to make the comments meaningful.  This record must contain
at least one non-blank character.

Data values are entered in record fields that are multiples of 10 bytes.
The following computer restrictions apply:

     -  Character data (e.g. zone names) are usually left justified and
        blank filled.  Sorted character strings must conform to the ASCII
        collating sequence.


                                                                     119
     -  All real values (i.e. with decimal points) can be placed anywhere
        in the 10 byte fields, but the decimal points must be included.

     -  All integer values must be right justified in the 10 byte fields.
        Their values must be within the range the computer is capable of
        handling.

While the file formats are defined as fixed size fields, variable formats can
be used, but numbers must be delimitted by commas and text fields must
be enclosed in """" pairs.

The maximum numbers of some data items that can be handled
are system parameters. Refer to the Appendix.

  A. 3 Description of File Formats
      ---------------------------

The formats for describing the data files in the following sections are
similar.

The number of bytes in the field is given at the start of the line.  If
there are several values in a format, this condition is indicated
differently (e.g. 8 x 10 implies eight fields of 10 bytes).

The information on the next line is the type of data in a field:

     byte     = character
     real     = number containing a decimal point
     integer  = number without a decimal point

                                                                     120

  A. 4 Format of attribute files
      -------------------------


  A. 4. 1 Preprocessing
          -------------

Attribute data are often obtained from Census Bureaux. These data are seldom
what is required, so will need processing before use.

Data often need normalising to allow for the differences in zone sizes. This is
done by arithmetic operations where new attributes are derived by dividing by
total population, area etc.

Also, data often need amalgamation e.g. census age groups to get the required
group.

  A. 4. 2 OzGIS Standard Format
          ---------------------

Attribute files contain the attribute value of each zone or line or site
for a number of attributes.  The names must correspond to those defined in
a geographic file.

The attribute description is used by OzGIS as a heading in a map
displaying the attribute.  The units description is used by OzGIS as a
heading to the class values in the map legend.

For efficient use of the system and to facilitate disc file management,
files should contain as many attributes as possible (to avoid having
separate files for each attribute).

Attribute files will usually be prepared by special programs which extract
data from a data-base and convert attribute values into the OzGIS
format.

     Comment Record:
     80       byte      comment describing the data

     Header Record:
     10       integer   number of attributes
     10       integer   number of names
     10       real      value used to indicate missing data

     Name Records:
     8 x 10   byte      names, sorted into ascending order

Sets of records follow to define the attributes:-

     Definition Record:
     30       byte      attribute description
     10       byte      units description

     Values Records:
     8 x 10   real      attribute values for zones, lines or sites in name
                        order

                                                                     121


  A. 4. 3 Sample attribute file DEMOATTR.DAT
          ----------------------------------

DEMOATTR.DAT   - ATTRIBUTES FOR SIMPLE 3 ZONE TEST MAP
         5         6     -9.9
ABCDEFGHIJZONE 1    ZONE 2    ZONE 3    ZONE 4    ZONE Z
FIRST STATISTIC               FIRST UNITS
       1.0       2.0       3.0       4.0       5.0       6.0
SECOND STAT                   SECOND UNITS
     100.0     200.0      -9.9     400.0     500.0     600.0
THIRD STAT                    3RD UNITS
       0.1       0.9       0.3       0.7       0.1       0.8
FOURTH STATS                  4TH UNIT
       1.0       2.0       3.0       3.0       2.5       1.5
FIFTH STAT                    5TH UNIT
       9.0       6.0       3.0       2.0       6.0       8.0

  A. 4. 4 Simple Attribute format (tabular database format)
          -------------------------------------------------


Many data retrieval systems (e.g. ORACLE,SAS) produce attribute data in a form
where for each attribute the names and their values are given.

This tabular format is supported in OzGIS although there are some restrictions
on its use.  The list of names is obtained from the first attribute; hence
no new names can occur in following attributes (although names may be
missing).  A set of data records for an attribute is assumed to finish (and
the next set start) when the attribute description & units changes.

     Comment record:
     80      byte       Comment describing the data

     Data records:
     10      byte       name
     10      real       value
     30      byte       attribute description
     10      byte       attribute units


  A. 4. 5 Sample simple attribute file DEMOSASA.DAT
          -----------------------------------------

SIMPLE FORMAT ATTRIBUTE FILE - DEMOSASA.DAT
TOP            1.0   DESCRIPTION A                 UNITS A
SQUARE         2.0   DESCRIPTION A                 UNITS A
DIAMOND        3.0   DESCRIPTION A                 UNITS A
TRIANGLE       4.0   DESCRIPTION A                 UNITS A
TOP            1.0   DESCRIPTION B                 UNITS B
DIAMOND        3.0   DESCRIPTION B                 UNITS B
SQUARE         2.0   DESCRIPTION B                 UNITS B
TRIANGLE       4.0   DESCRIPTION B                 UNITS B
TOP            1.0   DESCRIPTION C                 UNITS C
SQUARE         2.0   DESCRIPTION C                 UNITS C
DIAMOND        3.0   DESCRIPTION C                 UNITS C
TRIANGLE       4.0   DESCRIPTION C                 UNITS C

                                                                     122
TOP            1.0   DESCRIPTION D                 UNITS D
TRIANGLE       4.0   DESCRIPTION D                 UNITS D
DIAMOND        3.0   DESCRIPTION D                 UNITS D
DIAMOND        3.0   DESCRIPTION E                 UNITS E
TRIANGLE       4.0   DESCRIPTION E                 UNITS E


  A. 4. 6 Spreadsheet WK1 format (Lotus, Excel etc)
          -----------------------------------------


The WK1 file format is used to import/export data between OzGIS and spreadsheet
and database systems.

Refer to the chapter on the WK1 interface to systems.

Data from spreadsheets can be input in Lotus 1-2-3 format (WK1).

The spreadsheet must be set up in a fixed format:

The data values are in a matrix with the values for the zones (or sites or
lines) in columns and the different attributes across in the rows.
Values can be missing and can be integer or floating point.

The first column must contain labels which are the 10 character zone (site etc)
names, beginning at row 3. These must be SORTED in ascending order.

The top row contains labels that are the (up to) 30 character attribute
descriptions starting at column 2.

The second row is the 10 character attribute descriptions.
This is recommended but does not have to be present as some systems (e.g. MS
ACCESS) do not allow units to be defined.

e.g. the file DEMO123.dat can be read into the spreadsheet. It should look
like:

                 POPULATION GROWTH   SALES
                 NUMBER              $
ABBOTSFORD                 7418      237
BURWOOD E                  9925      955
CONCORD                    8984      202
CROYDON N                  9369      298
CROYDON W                   735
FIVE DOCK                  9903      716
HABERFIELD                           727
HOMEBUSH                   6631      704
HUDSONPARK                 4668       71
MORTLAKE                   1725      198
STRATHFIELD                6285      663
YARALLA                    9875      516

For example, with Microsoft Excel for Windows, the test file can be read by
choosing the option "Open" from the "File" menu and giving the test file as
\OZDEMO\DEMO123.DAT. A spreadsheet in the above format can be output by
selecting the "Save As" option from the "Files" menu and using the WK1 format
option.


                                                                     123

  A. 4. 7 ATLAS Data files
          ----------------

Attribute data files for the Atlas mapping system come as pairs of files, a
format file and a data file.

The first record of the format file is a map name, which is ignored.
There follows a a set of records, each of which gives the name of an
attribute. For example, the following file specifies two attributes:

"      Bundesland$"
"Population 1984        Totale Population in Tausend"
"Ausdehnung in qkm      Ausdehnung in Quadratkilometer"


The data files have one record for each map item. Each record starts with the
item name, and is followed by the values. The values are in the same order as
the attribute names and there is one per attribute (2 here). Values can be in
integer, decimal point or exponential formats. A value of 1.0E36 is missing
data. For example:

"SCHLES.-HOLSTEIN", 2615 , 157.21
"HAMBURG", 1.23E21 , 1.0E36
"BREMEN", 671 , 404
"NIEDERSACHSEN", 7230 , 47.447
"NORDR.-WESTFALEN", 16.777 , 34061
"HESSEN", 5548 , 21114
"RHEINLAND-PFALZ", 3627 , 198.48
"SAARLAND", 1052 , 25.71
"B.-WUERTTEMBERG", 9240 , 35751
"BAYERN", 10964 , 70552
"BERLIN", 1850 , 480

Names and attribute descriptions must be delimited by apostrophes as shown,
and values must be comma delimited. Only the first 10 characters of a zone etc
name is used and only the first 30 characters of a description.

Two data files have to be specified. The first is the format file,
the second the Atlas data file. The format file is handled as a parameter file
within the entry process so can be present on disk as a file named with
extension .PRM. In practise your two files will probably have the Atlas standard
file names with extensions FMT and DAT and you give the full file names when
asked for them.

For example, you might have a pair of files named EUROPE.FMT and EUROPE.DAT
so you give the parameter file as EUROPE.FMT and the data file as either EUROPE
or EUROPE.DAT (as DAT is the default extension).

  A. 4. 8 LAMM format
          -----------

The LAMM package was developed at the CSIRO Division of Building Research. The
format is supported as it is the only suitable format for mapping available in
the Australian Bureau of Statistics GEOSTATS system.

The first record gives the number of map items and the number of attributes

                                                                     124
respectively.

The attribute names follow, one per record

Finally the value records are given, being the name followed by the values.
The records are sorted into ascending name order. Values are separated by
blanks or commas.

An example file is DEMOLAMM:

12,8
MALES 35 - 44 (81)
MALES 35 - 44 (86)
MALES - UNEMPLOYED (76)
MALES - UNEMPLOYED (81)
MALES - UNEMPLOYED (86)
INCOME MALES $18001-$26000 (76)
INCOME MALES $18001-$26000 (81)
INCOME MALES $18001-$26000 (86)
'ABBOTSFORD'   69 0 14 27 48 0 51 55
'BURWOOD E'    223 0 48 134 89 0 218 397
'CONCORD'      102 0 5 12 29 0 109 197
'CROYDON N'    161 0 27 50 53 0 156 284
'CROYDON W'    180 0 24 36 76 0 307 241
'FIVE DOCK'    50 0 20 2 0 0 19 11
'HABERFIELD'   126 0 28 20 20 0 208 185
'HOMEBUSH'     114 0 26 51 37 0 165 212
'HUDSONPARK'   243 0 65 99 65 0 231 385
'MORTLAKE'     0 0 0 0 2 0 0 113
'STRATHFIELD'  100 0 4 7 10 0 74 70
'YARALLA'      7 0 16 2 0 0 4 3


  A. 4. 9 Comma delimited format
          ----------------------

The comma delimited format consists of a set of records:

Each record has a series of values separated by commas.

The first record gives the "column" names. The first is the map item names, and
the others are the attribute descriptions.

The following records are the data:

The first value is the item (zone,line or site) name and there follows one
number for each attribute.


The file DEMOCOMD.DAT looks like:

"ZONE","DOGS","CATS","BIRDS","RATS","FISH","HENS","SNAKES","COWS"
"Australia",1,0,0,0,36,40,0,400.123
"Europe",123.45,0,4,3,47,70,3,0


                                                                     125

  A. 4.10 Australian 1991 Census format
          -----------------------------


The Community profile floppy disk software from the ABS generates comma
delimited files that are the same as the above comma delimted format except
for an extra (second) column that gives a description for the Census regions.

The software drops the extra column.


  A. 4.11 Other attribute data formats
          ----------------------------

Other formats will be supported as required.

We will support any formats for major data suppliers, but you must send sample
data and documentation.

We will also attempt to support file formats from other packages.

                                                                     126

  A. 5 Text Attribute files
      --------------------

Text attribute files allow miscellaneous information to be attached to map
items and accessed during map interrogation

The file format is:

The first record is an 80 character comment

Sets of records follow for each map item:
   The item name (1-10 characters) preceded by $
   Any number of lines of text (up to 80 characters long)

The $ indicates the start of a new item

An example file is DEMOTEXT.DAT

A file could look like:

SALES TERRITORY DEFINITIONS
$Terr 1
North West NSW
Fred Smith
1991 Target $200,000
$Terr 2
Central Queensland
Salley Jones
1991 Target $320,000
$Terr 3
Tasmania
The Big Bopper
1991 Target $10,000

                                                                     127

  A. 6 Standard OzGIS formats for geographic files
      -------------------------------------------


  A. 6. 1 General Information
          -------------------

The standard data format reflects the internal topological file structure.

In practice, a complete data file is seldom available. It is more common to
bring in just points (as a map and points partition) or lines (as a map and
segments partition). Zones are usually formed from the segments by using the
zone/polygon building process.

Coordinates are usually given either in degrees (for lat,long) or in metres /
feet for UTM.

  A. 6. 2 Structure of data
          -----------------

Geographic files contain several partitions.  The first must be the map
partition, and can be followed by at most one of each of zones, polygons,
lines, segments and points partitions.

Each partition is preceded by a type record, which is one of MAP, ZONES,
POLYGONS, LINES or POINTS; for example, a zones file must  have the
following structure:

     Comment record
     MAP
     map records
     POLYGONS
     polygon records
     ZONES
     zone records
     SEGMENTS
     segment records

Different partitions are present (the MAP partition is always first)
 according to the type of data:-

Files which describe zones have a ZONES partition to define
the zones, a POLYGONS partion to give the polygons that
bound each zone (including lakes and islands), and a SEGMENTS partition
to define the coordinate points that draw the segments along the
polygon boundaries.

Sites files have a POINTS partition to give the site names
and locations.

Lines files have a LINES partition to define the line names
and a SEGMENTS partion to define the coordinate points in the
segments that make up the lines.

Line overlays are defined by SEGMENTS partitions.


                                                                     128
Marker and name overlays are defined by POINTS partitions.

Coordinate data should be entered in standard units.  Coordinate pairs are
always in the order (X,Y) (e.g. (Longitude, Latitude)).  Note that latitude
must be entered as a negative number in the Southern Hemisphere.

Data entered in latitude-longitude projection can be converted to other
projections.
Feature codes may be included to give a classification of geographic items.
e.g. segments may be classified as different types of roads.

All geographic regions (windows) are given in actual coordinate values in
the order:  X-minimum, X-maximum, Y-minimum, Y-maximum.

  A. 6. 3 Internal Data
          -------------

The geographic data are held internally as a word-addressable
random access disk file.
The file structure reflects the data structure with the necessary
indexing etc for processing.
Additional data are also generated for efficient processing:-

Polygons are held in display order so the map zones can be
rapidly displayed.

 A POINTS partition is generated internally by OzGIS
for the centroids of the zone polygons.
This enables markers or zone names to be overlayed over
a zones map, and for the points to be displayed as sites
where the site names are the zone names.

Lists of names are also generated for zones, lines or sites
for rapid retrieval.

  A. 6. 4 Comment Record
          --------------

     80      byte       comment describing the data


  A. 6. 5 Map Partition
          -------------

This partition contains general information about the file (map) and must
be the first partition.

     Type Record:
     3        byte      partition header = MAP

     Window Record:
     4 x 10  real       the region covered by the file

     Projection Record: (now redundant)
     10 integer         Map projection code
                        0=none, 1=lat-long degrees
     10       integer   type of zones (optional)
     10       integer   tolerance for joining line segments endpoints into

                                                                     129
                        polygons. Values range 0-3, usually zero
                        Used when endpoints calculated by spatial operations
                        e.g. polygon intersection, when arithmetic roundoff
                        can cause joining to fail


  A. 6. 6 Zones Partition
          ---------------

This partition defines the zones in the geographic region.

Each zone is defined by one or more polygons.  A zone may consist of a
polygon, several separated polygons, polygons with interior polygons of
other zones, etc.

If a zones partition is present, a polygons partition with the referenced
must be given.

The partition may be used as a polygon underlay and feature codes may be used
to give a classification e.g. the polygons may be different soil types.

     Type Record:
     5        byte      partition header = ZONES

     Definition Record:
     10       integer   number of zones
     10       integer   number of feature codes

     Feature code Records (if required):
     8 x 10  integer    feature codes

     Zone Records:
     10       byte      zone name, usually left justified, blank filled
     10       integer   number of polygons in the zone

     Polygon Records:
     8 x 10  integer    identifying numbers of the polygons

  A. 6. 7 Line Partition
          --------------

The partition defines networks of lines (e.g. roads, rivers).  Each network
has a name and is specified in terms of line segments.The name can be used
to apply quantised attribute data.

Type record:
     5       byte       partition Leader = LINES

Header record:
     10      integer    number of lines


Line record:
     10      byte       line name, usually left justified, blank
                        filled
     10      integer    number of segments forming the line



                                                                     130
Region Record:
     4x10    real       line limits (window)
                        X minimum, X-maximum, Y-minimum, Y-maximum)

Segments Records:
     8x10    integer    the identifying numbers of the line segments.

  A. 6. 8 Polygons Partition
          ------------------

A polygon defines an enclosed geographic area.  Each polygon is specified
in terms of the line segments which constitute its boundary.  If a zones
partition is given, every polygon referenced by the zones must be defined.

The centroid or internal point of a polygon is be used by OzGIS to
locate text (zone names) or graphic symbols;
a points partition is generated.

Type Record:
     8        byte      partition header = POLYGONS

     Header Record:
     10       integer   number of polygons

A set of records follow for each polygon:-

     Definition Record:
     10       integer   polygon identification number
     10       byte      name of zone enclosed by polygon
     10       integer   number of lines forming the polygon boundary
     10       integer   level of polygon for display using
                        polygon fill 0=standard, 1=lakes, 2=islands in
                        lakes etc. (range 0-5)

     Region Record:
     4 x 10   real      polygon limits (window)
                        (X-minimum, X-maximum, Y-minimum, Y-maximum)

     2 x 10   real      centroid or labelling point (X,Y) in the polygon
                        (set to centre of window if not given)
     10       real      area of polygon
                        (calculated if not given)

     Segments Records:
     8 x 10   integer   the identifying numbers of the segments + ve if
                        segment is clockwise, -ve if anticlockwise.

  A. 6. 9 Segments Partition
          ------------------

Line segments are defined by a set of points connected by straight lines.

Segments may define the boundaries of zones, define line
networks, or line overlays.

When a segment is a boundary segment of a polygon, it can be the boundary
of at most two polygons.
  In other words, the polygons must be a unique tessellation of the geographic r

                                                                     131

When the segments define polygon boundaries, the partition should contain
only the segments of the polygons, and the records must contain the names
of the zones on each side.  Left and right zones are defined by the
direction implied by the sequence of points in the line.  The zone names
must correspond to those defined in the zones partition.  The special zone
name OUTSIDE (left aligned)
should be used when the line is at the edge of the map, or on
the boundary of void areas.

Line segments (of polygons)
 must be closed (i.e., the last point in a segment must be the
first point of another segment), and segments must not cross or have loops.
Further, segment must not be repeated.

Segments that are to be used as geographic overlays may have feature codes to
give a classification e.g. different types of rivers.

Address information can be present. This consists of the name of the street
followed by 0, 1 or 2 sets of entries for street number ranges and postal codes.
These zip codes are optional as are the number ranges. If 2 ranges are given
one is odd and the other even numbers. The start and end values are given
according to the direction of the numbers and the digitising direction.

     Type Record:
     8        byte      partition header = SEGMENTS

     Header Record:
     10       integer   number of segments

A set of records follows for each segment.

     Definition Record:
     10       integer   identifying number
     10       byte      name of left zone (if line is part of a zone
                        boundary)
     10       byte      name of right zone (if line is part of a zone
                        boundary)
     10       integer   number of points in segment
     10       integer   number of feature codes
     10       byte      non blank indicates that address info follows
     10       byte      name of line network, default set to ldent number
                        this is also the name for interrogation

     Feature code Records (if required):
     8 x 10  integer    feature codes

     Address Records (if required):
     10       byte      name of street, park etc
     6 x 10  integer    start number, end number, postal (ZIP) code, followed
                        by optional second set

     Point Records:
     8 x 10   real      (X,Y) coordinate pairs (4 per record)

                                                                     132

  A. 6.10 Points Partitions
          -----------------

The partition contains a set of points or sites at which symbols can be
overlayed on the map.  The site name can be used to apply quantised
attribute data or used to annotate the points.

Feature codes can define a classification for display as sites.

Type Record:
     6        byte      partition header = POINTS

     Header Record:
     10       integer   number of points

     Point Records:
     10       real      X-coordinate value
     10       real      Y-coordinate value
     40       byte      site name or annotation
     10       integer   number of feature codes

     Feature code Records (if required):
     8 x 10  integer    feature codes

Note that only the first 10 characters are used for the site name.

  A. 6.11 Sample boundaries geographic file DEMOZSEG.DAT
          ----------------------------------------------

Geographic data for zones (e.g. Census districts) are usually brought in as the
line segments that form the boundaries of the zones.

The boundary segments contain the (X,Y) vertices that make up the line and the
names of the zones on each side of the line.


These data are usually entered via the IMPORT DATA FILES option in the top menu,
then excessive vertices discarded (thinned) using PREPARE DATA FOR DISPLAY, and
then the full zone / polygon/ line segment / centroids structure built using
BUILD TOPOLOGY FROM LINES SEGMENTS to prepare for display.

For example, to extract ZIP code boundaries from USA TIGER files, the left and
right ZIP codes are extracted from the records and formed into left aligned
zone names, and the latitude / longitude vertices are also extracted. If the
left and right zone names are the same the segments are internal to the zone
and can be ignored.

The following illustrates the standard format used to enter such data. Note
that the MAP partition is required but that the extent need not be given.

EXAMPLE ZONE BOUNDARY SEGMENTS THAT CAN BE BUILT INTO ZONES - DEMOZSEG.DAT
MAP
  0.0       0.0       0.0       0.0
         0
SEGMENTS
        10

                                                                     133
       107ZONE 1    OUTSIDE            2
102.00    503.00    114.00    503.00
       125ZONE 2    ZONE 1             2
102.00    503.00    110.00    513.00
       143ZONE 1    ZONE 3             2
114.00    503.00    110.00    513.00
       161ZONE 3    OUTSIDE            6
114.00    503.00    115.00    505.00    116.00    507.00    117.00    509.00
118.00    511.00    119.00    513.00
       187ZONE 2    ZONE 3             2
110.00    513.00    119.00    513.00
       205ZONE 2    OUTSIDE            4
119.00    513.00    114.00    518.00    109.00    517.00    104.00    516.00
       227ZONE 2    OUTSIDE            2
104.00    516.00    110.00    513.00
       245SURPLUS   SURPLUS            2
119.00    513.00    122.00    506.00
       263OUTSIDE   ZONE 2             2
103.00    509.00    110.00    513.00
       281OUTSIDE   ZONE 2             2
102.00    503.00    103.00    509.00

  A. 6.12 Sample segments file with adddresses DEMOADDR.DAT
          -------------------------------------------------

Address information can be added to line segments. Note the non-blank flag.

EXAMPLE  SEGMENTS (ROADS) WITH ADDRESSES - DEMOADDR.DAT
MAP
  0.0       0.0       0.0       0.0
         0
SEGMENTS
        10
       107ZONE 1    OUTSIDE            2            ADDRESS
Great North Road
         1       666      2600
102.00    503.00    114.00    503.00
       12            ZONE 1             2          ADDRHERE
Molonglo Gorge

102.00    503.00    110.00    513.00
       143ZONE 1    ZONE 3             2            address
Burra Street
         1        99         6        140
114.00    503.00    110.00    513.00
       161                             6            address
Northbourne Ave
         1        55      2602        20         66      2600
114.00    503.00    115.00    505.00    116.00    507.00    117.00    509.00
118.00    511.00    119.00    513.00
       187ZONE 2    ZONE 3             2
110.00    513.00    119.00    513.00
       205                             4            address
Yass rd
         1        99      2600
119.00    513.00    114.00    518.00    109.00    517.00    104.00    516.00
       227ZONE 2    OUTSIDE            2
EPPING HWY

                                                                     134
        44        22                  77         11
104.00    516.00    110.00    513.00
       245SURPLUS   SURPLUS            2            address
Hume Highway
         1        99      2301        88         44      2304
119.00    513.00    122.00    506.00
       263OUTSIDE   ZONE 2             2            address
Mains Avenue
         1        99      2600         6        140      2600
103.00    509.00    110.00    513.00
       281OUTSIDE   ZONE 2             2            address
Lover's Lane
        33        11
102.00    503.00    103.00    509.00

66 >> <SS>Sample geographic file DEMOZONES.DAT
The full topological geographic structure can be entered (although in practise
this is seldom available).

COMMENT LINE FOR TEST DATA     - DEMOZONE.DAT
MAP
102.00    122.00    502.00    518.00
         0
ZONES
         3
ZONE 1             1
       352
ZONE 2             2
       377       402
ZONE 3             1
       327
POLYGONS
         4
       327ZONE 3             3         0
110.00    119.00    503.00    513.00    114.00    510.00
       187      -161       143
       352ZONE 1             3         0
102.00    114.00    503.00    513.00    108.00    506.00
      -125       107       143
       377ZONE 2             3         0
102.00    110.00    503.00    513.00    104.00    508.00
      -263      -281       125
       402ZONE 2             3         0
104.00    119.00    513.00    518.00    110.00    515.00
       205       227       187
SEGMENTS
        10
       107ZONE 1    OUTSIDE            2
102.00    503.00    114.00    503.00
       125ZONE 2    ZONE 1             2
102.00    503.00    110.00    513.00
       143ZONE 1    ZONE 3             2
114.00    503.00    110.00    513.00
       161ZONE 3    OUTSIDE            6
114.00    503.00    115.00    505.00    116.00    507.00    117.00    509.00
118.00    511.00    119.00    513.00
       187ZONE 2    ZONE 3             2
110.00    513.00    119.00    513.00

                                                                     135
       205ZONE 2    OUTSIDE            4
119.00    513.00    114.00    518.00    109.00    517.00    104.00    516.00
       227ZONE 2    OUTSIDE            2
104.00    516.00    110.00    513.00
       245SURPLUS   SURPLUS            2
119.00    513.00    122.00    506.00
       263OUTSIDE   ZONE 2             2
103.00    509.00    110.00    513.00
       281OUTSIDE   ZONE 2             2
102.00    503.00    103.00    509.00


  A. 6.13 Sample lines geographic file DEMOLINES.DAT
          ------------------------------------------

A lines structure is used for line data that is to be displayed for attribute
data. Each line can be made up of several segments:

SAMPLE LINE NETWORK DATA       DEMOLINES.DAT
MAP
103.50    121.50    503.50    517.50
         0
LINES
         4
ROAD 3             3
110.50    119.50    503.50    513.50
       187       161       143
ROAD 1             2
103.50    114.50    503.50    513.50
       125       107
ROAD 2             2
103.50    110.50    503.50    513.50
       263       281
ROAD 4             2
104.50    119.50    513.50    517.50
       205       227
SEGMENTS
         9
       107                             2         0          ROAD 1
103.50    503.50    114.50    503.50
       125                             2         0          ROAD 1
103.50    503.50    110.50    513.50
       143                             2         0          ROAD 3
114.50    503.50    110.50    513.50
       161                             6         0          ROAD 3
114.50    503.50    115.50    505.50    116.50    507.50    117.50    509.50
118.50    511.50    119.50    513.50
       187                             2         0          ROAD 3
110.50    513.50    119.50    513.50
       205                             4         0          ROAD 4
119.50    513.50    114.50    517.50    109.50    517.50    104.50    516.50
       227                             2         0          ROAD 4
104.50    516.50    110.50    513.50
       263                             2         0          ROAD 2
103.50    509.50    110.50    513.50
       281                             2         0          ROAD 2
103.50    503.50    103.50    509.50

                                                                     136

  A. 6.14 Sample points geographic file DEMOPOINT.DAT
          -------------------------------------------

Points files just give the (X,Y) locations and a site name / label.

These files can be used with an attribute file for mapping site data or can be
used to place sysmols or labels at locations (overlays).

COMMENT LINE FOR TEST DATA     - DEMOPOINT.DAT
MAP
102.00    122.00    502.00    518.00
         0
POINTS
         3
114.0     503.0     PNT1
104.0     516.0     PNT2
114.0     518.0     PNT3


                                                                     137

  A. 7 Format of polygon geographic files
      ----------------------------------


  A. 7. 1 Standard (not implemented)
          --------------------------

Geographic data are often available in polygon format, and this data
definition enables it to be used used with OzGIS.

The common line segments on the boundaries of adjacement polygons are
effectively defined twice in polygon data; OzGIS assumes that they are
exactly the same.  The polygon boundary must not cross itself.

Each polygon has a name, which is the name of the zone to which it belongs.

Polygons may occur inside other polygons.  Where the polygon is not part of
a zone (e.g. a lake) it may be given the name OUTSIDE.  The level field
defines lakes, islands within lakes etc.  When maps are generated on
devices using polygon fill the level gives the order of display so the
polygons will overwrite correctly.


Comment record:

     80      byte       comment describing the data

Definition Record:
     10      integer    map projection code
     10      integer    zone type (optional)

Each polygon is defined by a set of records:

Polygon header:
     10      byte       zone name, usually left justified, blank filled
                        or OUTSIDE if an internal polygon.
     10      integer    number of points in the line
     10      real       level of polygon for hardcopy generation using
                        polygon fill 0=standard, 1=lakes, etc.

Centroid record:
     2x10    real       centroid or labelling point (X,Y) in polygon

Point records:
     8x10    real       (X,Y) coordinate pairs (4 per record) The last
                        point must be the same as the first.


  A. 7. 2 SAS Format Zone Files
          ---------------------

The SAS system provides a crude polygon format for map data. The old format has
been updated to allow for multiple polygons in zones and for data at several
levels of resolution.

The polygons must be given in the correct order for display when there are

                                                                     138
polygons within other polygons.

The data consists of variable length records with the following fields:

field1: the zone name
field2: the polygon number within the zone (usually 1)
field3: the X value
field4: the Y value

For example, part of a file might be as follows, where zone 19 has 2 polygons

  17   1 135.0198593289   -45.006152242
  17   1 135.0214474499   -45.008039698
  17   1 135.0234586746   -45.011447966
  17   1 135.0232417881   -45.011781529
  17   1 135.0146185011   -45.012796119
  17   1 135.0149845481   -45.012392245
  17   1 135.0148004219   -45.011233956
  17   1 135.0155192316   -45.009236805
  17   1 135.0140719935   -45.006661419
  19   1 135.0200279355   -45.018230647
  19   1 135.0211774409   -45.018684313
  19   1 135.0218305141   -45.017554402
  19   1 135.023555249    -45.017326832
  19   1 135.024860993    -45.014845043
  19   1 135.0251943022   -45.014588848
  19   1 135.0192894787   -45.023670658
  19   1 135.0179009587   -45.022158593
  19   1 135.0182676911   -45.021624267
  19   1 135.0180351585   -45.020997345
  19   1 135.0192095339   -45.020121485
  19   1 135.0194375813   -45.01857923
  19   2 135.0279172212   -45.023049563
  19   2 135.0281361789   -45.022784472
  19   2 135.0283748209   -45.0230802
  19   2 135.0285159498   -45.022607252
  19   2 135.0283438861   -45.023600549
  21   1 135.041364044   -45.0087376237
  21   1 135.039871216   -45.0095451251
  21   1 135.039485425   -45.0093839765
  21   1 135.037185282   -45.0106722265
            .
            .
            .
            .
            .

  A. 7. 3 Simple Format (old SAS) Zone Files
          ----------------------------------

Simple format files are in common use by the SAS system and other packages
providing SAS interfaces.  Polygon for lakes etc. should follow standard
polygons to provide the correct display order for overwriting.

This format has now been updated in the SAS system.


Each data record has the form

                                                                     139
     10      byte       zone name
     10      real       X coordinate
     10      real       Y coordinate
     10      integer    Polygon number within zone

  A. 7. 4 Sample simple zones data file DEMOSASG.DAT
          ------------------------------------------

SQUARE        3.0       5.0
SQUARE        7.0       5.0
SQUARE        7.0       10.0
SQUARE        3.0       10.0
DIAMOND       8.0       8.0
DIAMOND       10.0      5.0
DIAMOND       12.0      8.0
DIAMOND       10.0      11.0
TRIANGLE      13.0      5.0
TRIANGLE      16.0      10.0
TRIANGLE      19.0      5.0
TRIANGLE      13.0      2.0            2
TRIANGLE      15.0      2.0            2
TRIANGLE      14.0      4.0            2
SQUARE        4.0       0.0            2
SQUARE        8.0       0.0            2
SQUARE        8.0       4.0            2
SQUARE        4.0       4.0            2
SQUARE        0.0       0.0            2
SQUARE        5.0       1.0            2
SQUARE        5.0       3.0            2
SQUARE        7.0       3.0            2
SQUARE        7.0       1.0            2
OUTSIDE       15.0      6.0            2
OUTSIDE       15.0      7.0            2
OUTSIDE       17.0      7.0            2
OUTSIDE       17.0      6.0            2
TOP           4.0       8.0
TOP           19.0      8.0
TOP           19.0      9.0
TOP           4.0       9.0

                                                                     140

  A. 8 GIS / common geographic file formats
      ------------------------------------


  A. 8. 1 DIME format
          -----------

This format is supported, but has not had much use. The data are primarily 2
point segments, so is inefficient on storage.

Note that only 499 2 point segments can be handled.

The data are usually passed through BUILD ZONES?POLYGONS to build polygons and
then through PREPARE DATA FOR DISPLAY to join up the segments into ones of
decent length.

The data are long Ascii records, and look something like:

XX91609160012583                       1
  MANUEL              ST                       8    8      201   299   200
   29891600000011 14502 1450219711197119160       38  440195019510003016     234
  10003016     213   1818                        396750 757476396740
7574760610215040685606098370406849
  MANUEL              ST                       8    8      301   359   300
  35891600000029 14502 1450219711197119160       44  480195019510003016     233
  10003016     212   1818                        396740 757476396730
7574760609837040684906095020406848
  MANUEL              ST                       8    8      361   399   360
  39891600000037 14502 1450219711197119160       48  540195019510003016     233
  10003016     233   1818                        396730 757476396718
7574760609502040684806090470406846
  SCHOOL              ST                       9    9      900   998   901
   99991600000045 162   162  19720197209160       37  220200020010003031     107
  10003031     108   1818                        396611 755737396619
7557430605026045580006053140455632
  SCHOOL              ST                       9    9     1000  1098  1001
  109991600000052 162   162  19720197209160       22  140200020010003031     115
  10003031     115   1818                        396619 755743396624
7557460605314045563206054910455542

  A. 8. 2 DLG optional 3 format
          ---------------------

The DLG-3 format is the major interchange format in use, and data can be
obtained from many mapping agencies e.g. from USGS.

The data differs in concept from the usual data displayed by OzGIS in that it
is preclassified by the assignment of numeric "feature codes".

All identifiers are numbers. These are converted to names by left aligning
them in the 10 character name fields.

The data entry process processed the lines only. Any line with one vertice or
two vertices and the same node numbers is taken as a point.

Other lines are output with the left and right names set to the area names.

                                                                     141
Left and right area numbers of zero or one are taken to be outside the map.

Feature codes are stored as numbers (combined input pairs) for lines, points
and zones e.g. '291  22' becomes 2910022.

The first area is ignored as it should be the boundary of the map.

Polygons are generated by passing the geographic file through the zone building
process.  This carries the area feature codes through to the polygons, retains
the line segments, and forms a points segment that contains the centroids of
the polygons.

Note that file should have 80 character fixed length records. In practise files
often have no end-of-records (e.g. USGS CD-ROM files) or records may be
truncated. Records with end-of-line markers must no be more than 80
characters long.

Zero length records are not allowed.

You will find that DLG-3 files off ARC-INFO systems often have extraneous
background polygons that "zap" the map when displayed.

Some test files are supplied for Hawaii.  These were read off the USGS GeoDATA
CD ROM on a SUN system, and 'newline' characters inserted to form 80 character
records.  The files had to be edited as an arbitrary polygon was given as
outside the map as the left and right areas on the line (this could also be
handled during display by specifying feature codes).

The test files are:

HAWDLGWB - water boundaries i.e. the islands
HAWDLGWB - administrative boundaries
HAWDLGRD - roads
HAWDLGST - streams

The data format is described in the US Geological Survey Circular 895-c
"USGS Digital Cartographic Data Standards, Digital Line Graphs"

The files look like:

USGS-NMD  DLG DATA - CHARACTER FORMAT - 09-29-82 VERSION s21_wb.dlg
HAWAIIAN ISLANDS POLY 10 DROPPED        1967, 1980  2000000.
this record not used, cant be zero length
     3     3  9999     2 0.50800000000D+02     4     0     4     1
   0.637820640000000D+07   0.676865799729109D-02   0.800000000000000D+07
   0.180000000000000D+08  -0.157000000000000D+09   0.300000000000000D+07
   0.0                     0.0                     0.0
   0.0                     0.0                     0.0
   0.0                     0.0                     0.0
 0.10000000000D+01 0.0               0.0               0.0
SW       19.000000 -160.000000        -316386.41  1771715.66
NW       22.000000 -160.000000        -312489.03  2102112.53
NE       22.000000 -155.000000         208312.61  2101093.98
SE       19.000000 -155.000000         210917.63  1770684.40
WATER BODIES           0    74    74 010    12    12 010    70    70   1
N    1  -316386.41  1771715.66           0           0     0
N    2  -312489.03  2102112.53           0           0     0
N    3   208312.61  2101093.98           0           0     0

                                                                     142
N    4   210917.63  1770684.40           0           0     0
.
.
.
.
N   74  -320966.08  2105481.92           2           0     0
   -69    70
A    1   -68438.87  1949336.24           3     0     1     0     0
     8     9     7
     0     0
A    2  -327997.34  2094827.63           3     0     1     0     0
   -10    -2    -1
    40   150
.
.
.
.
A   13   -91708.84  2025480.45           3     0     1     0     0
   -66   -65   -67
    40   150
L    1     7     6     2     0                24     1     0
  -332906.23  2078428.77  -332805.62  2077920.57  -331991.53  2078579.38
  -332446.45  2079748.67  -331479.96  2080407.19  -331224.96  2080914.69
  -331578.38  2082032.98  -331221.19  2082845.09  -330100.11  2084620.90
  -329235.22  2085279.61  -328573.03  2086192.72  -328571.24  2087107.12
  -327247.56  2088577.74  -325977.26  2088727.66  -325164.16  2088878.47
  -324909.37  2089284.37  -324503.57  2088978.78  -323182.17  2089280.99
  -322319.07  2089025.30  -321707.68  2089938.51  -321250.68  2089836.02
  -320995.88  2090241.92  -319775.79  2090696.74  -318961.20  2091609.55
   290  4000
.
.
.
.
L   70    74    66    11     0                 2     1     0
  -320966.08  2105481.92  -321422.78  2105736.82
   290  4002

  A. 8. 3 Gina format
          -----------

The standard interchange format for GeoVision GIS is Gina.

Only some of the data file is processed. Feature codes must be numeric. Zone
names generated are of the form ZONE12345 and site names are of the form
POINT12345.

Only boundary lines and points are output - you have to generate
the zones / polygons afterwards.

The sample file DEMOGINA.DAT is as follows:

udb-start b v 8192

udb-header 0.5 fred-db "Fred's test database"
descr      29oct85 14:32:10 example GINA files
coord-sys  rect  feet
extent -12000, -8000,  12000, 8000

                                                                     143
layer 1 base        "base information layer"
layer 2 roads       "roads and streets layer"
layer 3 hydro       "hydrographic layer (rivers, streams etc)"
layer 4 telephone   "telephone plant layer"
layer 5 lots        "property lots layer"

network 1 emergency l 2 "emergency routes"
network 2 property  p 5 "property polygon network"

udb-primary
table road free
field name        char 40   i n   "road name"
field r_type      char 12   i n   "type of road, arterial, highway etc"
field lanes       num  2,0        "maximum number of lanes"
field surface     char 10   n     "type of surface"
fc   1000, 1099
table house free
field h_type      char 10   n     "house type: bungalow;""test quotes""  etc"
field lot_no      num 10    i     "lot number"
fc   1130,  1139
table lots free
field lot_no      num  10   i u n "lot number"
field address_no  num  6,0  i n
field street      char 40   n     "street name"
fc   1100


udb-feature
feat 1  1002 2 0 l xy 0 0 0 1 0
coor 1805 1120 1805 1143
coor 2018 1143 2018 1204 2508 1204
text "Elm Street"
attr Elm suburban 2 "asphalt"
feat 2  1004 2 0 l xy 0 0 0 1 0
coor 2508 1204 2508 820
text "Oak Street"
attr Oak arterial 4 "concrete"
feat 3  1400 5 2 l xy
coor 2508 903 2508 933
feat 4  1400 5 2 l xy
coor 2508 933 2568 933
feat 5  1400 5 2 l xy
coor 2568 933 2568 903
feat 6  1400 5 2 l xy
coor 2508 903 2568 903
feat 7  1400 5 2 l xy
coor 2508 873 2508 903
feat 8  1400 5 2 l xy
coor 2568 903 2568 873
feat 9  1400 5 2 l xy
coor 2508 873 2568 873
feat 20  1100 5 2 p xy
coor 2520 920
attr  10875,  104 Oak
feat 21  1133 5 0 l xy
coor 2530  920
attr 2-story  10875
feat 22  1100 5 2 p xy

                                                                     144
coor 2520  890
attr 10874,  106 Oak
feat 23  1133 5 0 l xy
coor  2530 890
attr bungalow 10874

udb-polygon
poly 3 20 r e
poly 4 20 r e
poly 6 20 l e
poly 5 20 r e
poly 6 22 r e
poly 8 22 r e
poly 9 22 l e
poly 7 22 r e

udb-indirect
table road_types free
field r_type    char 12 i u n  "road type"
field maint     char 2         "maintenance class"
field resp_code char 3  n      "responsibility code"
attr highway    m3  A-4
attr aterial    m6  B-3
attr secondary  n2  B-1
attr suburban   s4  B-8


udb-indirect
table house_types  free
field h_type    char 10  i u n "house  types"
field tax_code  char 4   n     "taxation code"
attr bungalow  10-5
attr 2-story   12-2
attr split     11-5

udb-end

  A. 8. 4 ANSII standard
          --------------

The new standard format for interchange will be supported when test data become
available.

  A. 8. 5 SIF format (not available)
          --------------------------

SIF format will be supported if there is a demand.
Data files appear to be 80 character ascii files.

The files contain a series of commands that define how the coordinates are to be
displayed.

Most of the commands are ignored.

The commands of value seem to be:

DID/ is the first record in the file, and gives some basic information. The
parameter MO=2 or MO=3 gives the number of dimensions (compulsory?). Any Z value

                                                                     145
is ignored.

OVR/   defines the active level. This is stored in the relations as a number
column 'ovr' as it seems to  be  effectively a layer.

ASC/ggnum defines the graphic group number, and is used to  form the entid of
form SIFggnum.

If ggnum is 0 the item is ignored (not appended).

If ggnum is <0 a number is assigned to it (sequentially starting at 10001).

LST/xx, defines a line. There are 2-101 vertices in a record. If a record has
101 values and the next record starts with the same point as the end point it is
taken to be a continuation. (actually found some records with more than 101)

LST/ and LST/OP are line strings.

LST/HO and LST/SO are polygons (solid & holes)

Vertices are (x,y) or (x,y,z) according to the DID/ header.

New records that are not continuations are taken to be new components.



  A. 8. 6 DXF format
          ----------

Digitised map data can be entered into OzGIS in the AutoCAD Drawing Interchange
and File format as lines, points and polygons.

The format is described in the AutoCAD manuals.

If the data are to be used for choropleth mapping (with attribute data) the
entities must have been digitised  with handles to give the entities names. The
hexadecimal handle values will become the zone (or point) names that will also
have to be used in the attribute files. You can rename the  entities with a
combine file by using the data reparation process, but the the easiest method
is to edit the names with a word-processor. The names are treated as text. The
handles are given in type 5 groups.

The entities are processed as follows:

LINEs are stored as line segments, and can only be used for line overlays
as there is no left & right zone names to enable polygons to be built.

POINTs are stored as points. Any handle will be used as the name.

POLYLINE & VERTEXes give a series of points that are either lines for line
overlays, or polygons if a bit flag values defines it as closed. If a
handle value is given it becomes the name and attribute values can be linked
to it (polygons).

TEXT entities are stored as points with the text group used as the name
or for assigning attribute values (first 10 characters).


                                                                     146

  A. 8. 7 Digital Chart of the World
          --------------------------

    The Digital Chart of the World is a 1.7 GB digital geographic database that
is available on CD-ROM.  Like most US government data it is public domain,
price about US$200!

 More than 200 different types of attributes present worldwide are logically
organized into 17 thematic layers.  Since each thematic layer may contain
information in the form of points, lines, and/or polygons, there are up to 27
possible coverages present.  In addition to the attribute information most
layers contain one or more levels of annotation.  Most of the annotation
contains place name information for cities, mountains, lakes, or other
geographic features.  Other types of annotation supplement attribute coding or
contain data quality information.  The original text size and location
information are retained, thus allowing the production of publication quality
maps.  The major thematic layers in the DCW database include international
boundaries, hydrography, elevation, populated places, roads, railroads, utility
lines, airports, cultural landmarks, physiography, supplemental data, and data
quality.

The Digital Chart of the World  was input from 1:1,000,000 Operational
Navigation Charts and 1:2,000,000 Joint Navigation Charts.  It includes 17
layers, aeronautical info, data quality info, drainage, supplemental drainage,
hypsography, hypsography supplemental, land cover, ocean features,
physiography, political/ocean, populated places, railroads, transportation
structure, utilities, and vegetation.

The data comes on 4 CD-ROMs and includes a BROWSE database for superficial views
of the whole world, and 4 detailed databases.

The detailed databases are split into 5 degree square tiles.

Ponts, lines and text data can be imported as DCW files. Lines can be built
into polygons with some restrictions.

A CD-ROM drive does not have to be on-line; files can be copied from another
PC.

Refer to the complete chapter on DCW processing.


  A. 8. 8 IDRISI Vector Format
          --------------------

Vector overlay files from the IDRISI raster GIS system can be entered.

The files have a simple format of the form

ident,number vertices
X,Y
. .
. .
X,Y

Where a 0,0 record indicates end of data

                                                                     147

Points, lines or polygons can be entered.

Only records with one vertice will be processed for points, with more than one
vertice for lines, and more than two vertices for polygons.

Three sample files are supplied for deaths during the 1854 London Cholera
outbreak. These are STREET.VEC, DEATH.VEC and PUMP.VEC. See the associated
*.DVC decumentation files for details.

From NCGIA, Santa Barbara. Digitized in 1992 by Rusty Dodson from the map
included in the book by John Snow:  "Snow on Cholera...", London:  Oxford
University Press, 1936.

A trivial two line file could be:

1 2
16.7380009 18.6959991
17.6599998 18.7119999
36 3
11.3450403 4.9679508
11.0809002 4.4880772
11.6251144 3.5709989
0 0

  A. 8. 9 ATLAS Export Format
          -------------------

Digitised boundary data can often be purchased in a format supported by the
Atlas PC mapping system.

The files are Ascii, and records are of the form:

"name",n,x1,y1,...........Xn,Yn

where

n=1 => a point
n=2 => a circle
n>2 => a polygon
n<0 => a line

These data can be entered via the OzGIS system with some restrictions:

. circles are not supported

. only the first 10 characters of the name can be used to assign attribute
  values.

. there cannot be more than one spatial object in a record

. The name of a polygon that is internal e.g. a lake, should be "OUTSIDE".


An example file for africa AFRICA.DAT may be included with your system.

Example file records from the africa files are:


                                                                     148
"Morocco",141
13.92683,60.72203
13.92685,60.67901
13.99129,60.48547
14.1201,60.33495
14.24891,60.18444                       A POLYGON
14.3777,60.07695
14.48501,60.05548
14.61376,60.07703
14.72104,60.09858
14.80687,60.14163
    .
    .
"Tunisia",113                          A ZONE with 2 polygons
24.03397,61.15581
   .          .    polygon 1
   .          .
24.03397,61.15581
25.49409,58.66141
   .          .    polygon 2
   .          .
25.49409,58.66141
24.03397,61.15581   < - first point repeated after every polygon


    .
    .
"Mbabane",1
41.41317,7.313157
"Maseru",1
38.45704,4.957369                       POINTS
"Pretoria",1
39.15494,8.036585
    .
    .
    .
"euro3",-41
33.15051,61.9
33.10709,61.72918
33.14988,61.68601                       A LINE
33.21407,61.62125
33.34267,61.55629
    .
    .
    .
Atlas seems to handle multiple polygons within a zone by simply putting them
all together in the record following the name i.e. if the first vertex is
found to be equal to another in the following list, then that is the end of
that polygon and the next vertex is the start of the next polygon etc. For
some strange reason the first point of the region is repeated after each
of the polygons.

Atlas does not support topologically structured polygons, so ensure that
internal polygons are given after the containing polygons so they are not
overwritten on the screen. Also, internal polygons that are to have the
background colour should have names "OUTSIDE".

Apparently there are two possibilities for regions with multiple polygons:

                                                                     149

The polygons can be kept together, which results in the format which you
see in the africa-files (see below). This is the default! The other
possibility is to split the the region into separate polygons. This results
in an export format where each polygon starts with the boundary name, number
of vertices and then the vertices. (The easiest way to do this in ATLAS is
to SELECT ALL, and then BOUNDARY, SPLIT, ISLANDS.)

The following is supposed to be from the ATLAS EXPORT/IMPORT MANUAL:

ISLANDS AND LAKES

The Island/Lake Rule
--------------------

If you return to the firs coordinate pair in the description of a region,
you have closed the main polygon. The line to the next coordinate pair
will not be drawn, but will instead signal the start of an island or lake.
The last coordinate pair in the island or lake must be the same as the first
one; this must also be followed by the first coordinate pair of the main
polygon - this line again will not be drawn. This rule may be applied as
many times in succession as necessary, one time for each island or lake.

Curves created with Atlas*Draw can also have islands, but ASCII boundary
files do not support this.

General Region Structure With Island/Lake
------------------------------------------

The format for a region containing an island and/or lake is:

"Pname","Sname",numxy
x1,y1
..
xn,yn
x1,y1
xx1,yy1,
..
xx1,yy1
x1,y1

The second xx1,yy1 pair closes the island or lake and is immediately
followed by an x1,y1 pair, which closes back to the main polygon.
Additional islands or lakes can follow, as long as each closes on itself
and then closes back to the main polygon.

The illustrations below show examples of a region with an island, and of a
region with a lake containing an embedded region.

The region with an island is listed as:

"Region w/Island",11
1,1 first coordinate pair
1,0
0,0
0,1
1,1 end of main polygon
2,1 start of island

                                                                     150
3,1
3,0
2,0
2,1 end of island
1,1 end of main polygon

An entry for a region with a lake containing an embedded region:

"Region w/lake",11
0,3 first coordinate pair
3,3
3,0
0,0
0,3 end of main polygon
1,2 start of lake
1,1
2,1
2,2
1,2 end of lake
0,3 end of main polygon
"Embedded Region", 5
1,2
2,2
2,1
1,1
1,2

According to the documentation, regions with multiple polygons can name
them all with a record of the form e.g. "poly1","poly2","poly3",num
The data we have seen does not seem to do this, but just gives one name.



  A. 8.10 MapInfo Data Interchange Format
          -------------------------------

Many data suppliers can provide geographic data in a format suitable for use
with the MapInfo mapping system.

This format is partially supported, primarily for Census boundaries.
The main restriction is that the more contrived spatial types are not supported.

The data is supplied usually as two files. The MapInfo Interchange File (MIF)
contains the coordinates. The other file, the MID file, contains data, of which
the only part of interest is the names of the spatial objects. Hence the MID
file has to be given if you want to display attribute data, such as Census
data, according to the names. Optionally the MID file need not be given, in
which case the lines, points and polygons can only be used as overlays.


The MIF file starts with a header of the form:

             Version 2
             Delimiter ","
             CoordSys Earth Projection 1, 0
             Columns 2
               Name Char(40)
               ID Integer

                                                                     151
             Data

The only parts of the header used are:

"Delimiter" defines the seperator used in the MID file, default <tab>

"Columns" gives the number of values in the MID file for each object

"Data" indicates the end of the header and start of the coordinates etc

The data part of the file describes several types of objects. Only real
geographic types are processed:

POINT and CENTER describe points (sites)
LINE and PLINE describe line segments
REGION describes zones (polygons)

Entries such as PEN are ignored.

A typical Census boundary file will have region entries with coordinates that
will be output as polygons and centre's output as points. The polygons and the
points will both have the same names from the MID file, so Census data can be
mapped as either zones or sites, and the polygons and points can also be used
for overlays e.g. to put names on the polygons.


For example, the data part of a MID file could look like:

Region 1
  41
147.30982 -42.851953
147.309298 -42.851559
147.309174 -42.851233
147.309033 -42.851096
147.308207 -42.851211
       .       .
       .       .
       .       .
       .       .
       .       .
       .       .
147.312079 -42.850697
147.310575 -42.851964
147.30982 -42.851953
    Pen (1,2,12582912)
    Brush (2,16777215,16777215)
    Center 147.308418 -42.848512
Region 1
  13
147.286268 -42.838088
147.282985 -42.841294
147.283788 -42.842113
147.285434 -42.843622
147.286394 -42.844522
147.28709 -42.845175
147.289192 -42.847147
147.290486 -42.84662
       .       .

                                                                     152
       .       .
       .       .
       .       .

The MID file provides the names of the objects as "columns". You will have
to provide the number of the column that is the names (usually 1)

If a polygon  is inside another it should have the name "OUTSIDE" so it
will be displayed with the background colour.

A MID file with the name in column 1 looks like:

Canberra,637
Burra Creek,639
Phred,640
London,641
Wagga Wagga,642
1230807,644
  .
  .
  .


                                                                     153

  A. 9 Format of names files
      ---------------------


Names files give lists of zones, lines or sites which are to be used to
restrict certain kinds of processing in OzGIS.

The file would usually be prepared with a text editor, possibly operating
on a file output from OzGIS.

     Comment Record:
     80       byte      comment describing the data

     Name Records (one per zone or line or site)
     10       byte      name


  A. 9. 1 Sample names file DEMOATTR.DAT
          ------------------------------

DEMONAMES.DAT - NAMES FILE
ZONE 1
ZONE 2
ZONE 4


  A.10 Format of colour names files (Removed from system)
      --------------------------------------------------


Colour names files are usually generated within OzGIS, but they may be
entered as data files. The file X11-BGR is supplied.

Comment record:
     80      byte       comment describing the file

Colour records:
     40      byte       colour name (in ascending order)
     10      real       blue value, range 0.0 to 1.0
     10      real       green value, range 0.0. to 1.0
     10      real       red value, range 0.0 to 1.0

The demonstration file DEMOCOLNM.DAT looks like:

DEMO COLOUR NAMES FILE
aquamarine                                   .8314    1.0000     .4980
blue                                        1.0000     .0000     .0000
brown                                        .1647     .1647     .6471
darkseagreen                                 .5608     .7373     .5608
hotpink                                      .7059     .4118    1.0000
lemonchiffon                                 .8039     .9804    1.0000
lightskyblue                                 .9804     .8078     .5294
mintcream                                    .9804    1.0000     .9608
pink                                         .7961     .7529    1.0000
purple                                       .9412     .1255     .6275
royalblue                                    .8824     .4118     .2549

                                                                     154
salmon                                       .4471     .5020     .9804
steelblue                                    .7059     .5098     .2745
turquoise                                    .8157     .8784     .2510
yellowgreen                                  .1961     .8039     .6039


  A.11 Format of combine files
      -----------------------


Combine files define new map zones in terms of zones in a base map, or site
catchments in terms of percentages of base zones.

Comment record:
     80      byte       comment describing the file

Header record:
     10      integer    number of items defined


Sets of records follow for the items:

Item definition record:
     10      byte       name (ascending order)
     10      integer    number of zones

Zone records:
     10      byte       zone name (ascending order)
     10      real       proportion of zone in area (0 to 1.0)



  A.11. 1 Sample combine file DEMOCOMB.DAT
          --------------------------------

This file defines three territories AREA1, AREA2, AREA3 in terms of base zones
A, B, ......

3 AREAS
         3TEST AREAS
AREA1              1
H             1.0
AREA2              3
N             1.0
O             1.0
R             1.0
AREA3              5
A             1.0
B             1.0
C             1.0
D             1.0
E             1.0

  A.12 Format of presentation files
      ----------------------------


Presentation files give a set of saved map files that are to be referenced

                                                                     155
by menu items so the maps can be easily displayed when giving demonstrations.

Presentation files must have names with extension prs e.g. DEMO.PRS

     First record:

     60      byte       menu header

A pair of records is given for each saved display file
     60      byte       menu item text
     50      byte       saved map file in full form


  A.12. 1 Sample presentation file
          ------------------------

AURISA Exhibition
Far East Asia zone map
DEMOFEA.SAV
Lowe Electorate bivariate zone map
BIVLOWE.SAV
Diagram map
DIAG1.SAV
Zones & Sites map
ZONESITE.SAV
Australia Statistical Division zones map
DEMOOZ.SAV
Canberra LGAs zone map with overlays
ACT.SAV

  A.13 Format of marker files
      ----------------------


Markers are displayed in OzGIS as single polygons using polygon fill.

OzGIS has standard files available (star, triangle etc.) but a you can
define your own.

A marker is a single closed polygon.  OzGIS requires that the points that
define the polygon lie within a circle of unit diameter.

The data points are usually prepared by drawing the marker on graph paper,
centred on the origin, and lying within a circle of radius 0.5.

     Comment record:

     80      byte       marker name, comments

     Header record:

     10      integer    number of points (3-100)

     Boundary record:

     8x10    real       Polygon points (X,Y) 4 per record
                        Values are in the range (-0.5 to +0.5)  The last
                        point must be the same as the first

                                                                     156


  A.13. 1 Sample marker file SQUARE.DAT
          -----------------------------

SQUARE.DAT - MARKER
         5
-0.35     -0.35     -0.35     0.35      0.35      0.35      0.35      -0.35
-0.35     -0.35

  A.14 Format of device files
      ----------------------


Device files describe the characteristics of graphics display devices and set
colours etc.

Standard files are usually held on the system for all devices available. Users
would not usually define their own.

 OzGIS was designed to operate as a highly interactive colour mapping system
where speed of display was obtained by the use of an  advanced raster display
system.

 The software can operate on most graphics devices, but there could be loss of
speed and capabilities depending on the characteristics of the devices being
used.

 OzGIS is based on graphics packages with the functionality of the GKS graphic
standard. These graphic packages provide graphic primitives such as lines,
text, and filled polygons. An important feature of GKS is that it is device
independent so the package allows OzGIS to produce maps on a large range of
devices.

 Every device available for use with OzGIS has at least one file associated with
it.

All devices within OzGIS have the same characteristics so e.g. a map previewed
on a display device can be output directly to a hard-copy device. The files
ensure that a device with limited capabilities can  simulate the required
capabilities in the best way.

 The device files also set GKS primitive attributes such as colours and zone
fill types. A colour display system has several files available that provide
standard sets of colours for maps. Files with similar colours are usually
available for different devices for hard-copy generation.

The easiest way to generate device data files is to edit standard ones.

The device files require colours to be specified in blue,green,red. One way to
decide on these values is to look at the definitions in the colour names data
file \ozgis\x11-bgr.dat.

When outputting to a printer under WINDOWS you will find that you need a device
file with a white background. Also, some printer drivers only show text that is
black or white. The background is always assumed to be just the paper i.e. it is
not coloured.


                                                                     157
Hardcopy device files are based on the SCIPLOT package which has a fixed set of
colours. Of course plotter colours depend on the pens. SCIPLOT colours are:
     Black
     Blue
     Green
     Cyan
     Red
     Magenta
     Brown
     Light Gray
     Dark Gray
     Light Blue
     Light Green
     Light Cyan
     Light Red
     Light Magenta
     Yellow
     White



     Comment record:

     80      byte       Device description


     Size record:

     10      real       Extent of device surface
     Note: defines units used for all sizes in data i.e. divide by this
     10      real       width of device in device units (now set from OZGIS.INI)
     10      real       max address height of device    (now set from OZGIS.INI)

     Type record:

     10      integer    GKS workstation number
     10      integer    Display type, 1 = raster display, pixel addressed
                                      2 = continuous coordinates
     10      integer    Fill type, 1 = solid colour
                                   2 = pattern
                                   3 = device hatching
                                   4 = OzGIS hatching for OzMAP etc
                                   5 = colour simulation for 4 pen plotter
     10      integer    Locator device number, 0 = none, 1 = default
                                               2 = crosshairs

     Advanced Raster Record  (now set fromOZGIS.IN)

     10      integer    number of bit planes (1-24)
     10      integer    length of LUT (1-4096)
     10      integer    number of pixels across screen (256-4096)
     10      integer    number of lines on screen (256-4096)
     10      integer    run-length encoding/decoding, 0 = not available

     Colour definition record:

     10      integer    number of colours defined


                                                                     158
     Colour table records:

     10      real       blue value (0.0 - 1.0) for colour table
     10      real       green
     10      real       red

     Hatch definition record:

     10      integer    number of hatch patterns (0 - 256)

     Hatch records (if required):

     10      integer    line number (1 - 8)
                        (from overlay and quant. lines)
     10      real       line angles (0.0 - 180.0)
     10      real       line separation  (<0.1)
     10      integer    line number (0 - 4) , 0 = not used
     10      real       second line angle (if reqd)
     10      real       second line separation (if reqd)

The rest of the data records set internal tables for GKS primitive
attributes.  Most records reference the colour table; the index has range 1
to length of table.


A style table is used with the colour table for polygon fill according to
the fill type.

-  SOLID - the colour is used, style not relevant
-  HATCH - the pen colour is obtained from the colour table, the hatch
           pattern number from the style table
-  PATTERN - the colour table is not used, the style table gives the device
             dependent pattern number

Area Fill records:

10   integer            colour index
10   integer            fill or style index

Several fill records are required, in following order:

-  background. NOTE also the menu / messages/ everything colour
-  zone missing data
-  excluded zones
-  diagram background
-  line or site quantisation legend and diagram
-  8 polygon underlay records

Text records:

10   integer            colour index
10   integer            font number  (1-9)
10   integer            text precision 0=STRING, 1=CHAR, 2=STROKE
10   real               height of character space (pixels)
10   real               width of character space  (pixels)

Note:  the DOS version uses sizes that are a multiple of 8 pixels, and will
adjust the size accordingly e.g. 8X8, 16X16, 16X8.

                                                                     159

Fonts are available for use on the screen, but are more usually used for output
on plotters.

The following fonts are available:

For OzMap and DOS version:

1 VGA/EGA hardware font or default hardcopy font
2 Simplex Roman, the most basic
3 Duplex Roman, more detailed than the simplex with about twice as many strokes
4 Complex Roman, similar but with more tapered segments
5 Triplex Roman, heavier version
6 Simplex script, based on handwriting
7 Complex script
8 Complex italic italic version of complex roman
9 Triplex italic

The windows fonts are defined in the \ozgis\ozgis.ini file

The text records are:

4 records to define the text available for name overlays at sites or typed
in text.
The text is usually defined in increasing size order.

Legend text record:  This is fixed size text used for generation of all the
legends.  The size is very important as it governs the overall size of the
legend e.g. the zone legend boxes are 3 times the text height in height, 2
times the text width in width.

Attribute description text record:  This is normally large text.  The
interactive system has to be able to clear it off for each attribute so it
should be fixed size hardware text in that case.  When two variates are
displayed the two descriptions are separated by
 a 'VS' or 'AND' generated using the
legend text.


Line records:

10   integer            colour index
10   integer            GKS type (1-4)
                        1 = solid, 2 = dashed, 3 = dotted, 4 = dash dot

The actual records are as follows:

4 records for lines to be used for line overlays.

4 records for lines to be used for quantised lines (line-type has no
meaning here as types are assigned according to quantisation).

Note that these first 8 records also define the hatching
plotter 'pens' if applicable.

A record to define zone boundaries line.

A record to define the line used to draw axes on diagrams (should be

                                                                     160
solid).

A record to define the line used to draw statistical values on diagrams.

Marker records:

10     integer     colour index
10     integer     fill style index
10     real        marker height (and width)
40     byte        marker file name, left aligned, system format

The records are as follows:

4 records for markers to be used as overlays at sites.

4 records for markers used for sites with quantised attribute data (marker
size has no meaning, is set for class).

1 record for site marker background  (currently not used)

1 record for scatter diagram (GKS marker no 1)

Colour Sequence records (170 records):

10     integer  colour index
10     integer  style index

These records give sequences of colours (or patterns) or hatching for
colouring zones after quantisation.

There are two types of sequence:

-  a 121 value array for single variate zones followed by
-  a 7x7 array for bivariate


The class fill is found by sampling out of the sequence for the number of
classes, e.g. for bivariate

2 classes         1        7
3 classes         1   4    7
4 classes         1  3  5  7

Similarly, the single variate 121 value array allows exact sampling for
number of classes 2-7; a best choice is made for 8,9 or 10 classes.  In the
special case of pseudo-continuous colour maps the whole 121 values are
used.

Menu colour records (graphics mode, fixed for text mode)

10 integer background text number (1-8)
10 integer foreground text number (1-8)

The menu colours are:

1 main menus
2 lists
3 help messages

                                                                     161
4 input of values
5 error messages

The 5 menu records for DOS use internal text numbers


From version 10.7, the standard WINDOWS colours are used for the user interface

The following no longer applies:

The following 5 records for WINDOWS reference colours in the usuual way.
WINDOWS system colour records follow for the GUI elements such as windows
titles, scrollbars, buttons etc (some elements such as arrows dont seem to be
supported). Video boards with 16 colours seem to have fixed colours, and
apparently the hardware colour table is never rewritten. A guess at these
colours is in the file WINSV.DAT, which uses the default WINDOWS colours. Video
boards with 256 colours are rewritten.



Note:  Files for advanced raster display systems with long LUT's should be
set up as follows:

-  Display type = 1
-  Fill type = 1
-  LUT length 256 or greater
-  One LUT colour for each record in the data file i.e. all colour index
   values unique

The system by passes the colour index and style index when operating in
fast interactive code and accesses the LUT directly.

                                                                     162
                     B. USA Census data
                       ===============





This appendix describes the procedure for entering US Census Bureau CD-ROM
files into the OzGIS system, and gives examples of the procedures to
prepare data and display maps.






  B. 1 Overview
      --------

The Census Bureau supplies data on CD-ROM. There are two types supported:

1. the population and housing Census data (STF1A files), one State
   per CD-ROM

2. the digitised map data (TIGER format) supplied as one County per
   CD-ROM

The data entry process provides the facilities to input these data, BUT...

THE FILES MUST BE NAMED IN THE CORRECT WAY as described later.

The CD-ROM files can be very large, but the internal OzGIS files are much
smaller. Hence the  usual procedure will be to read the raw data files
directly off CD-ROM. Processing can take some time.

The basic facility provided in the OzGIS system is to map tract/BNA or
block group level data on a County basis. Census data can be extracted
into one attribute file for one or more Counties. Census boundaries can
be extracted into separate files for each county. Multiple county maps
are generated by mapping the single attribute file with multiple geographic
files.

Data for map overlays (e.g. roads) can also be extracted from TIGER data.
These data can be displayed without Census data.

Other data could be extracted from the CD-ROMs (e.g. blocks, places) and
will be supported if there is demand.

The capacity of the OzGIS system can be exceeded by these data. This
should be less of a problem with the WINDOWS version as it uses extended memory.
The capacity should be sufficient to produce tract/BNA maps with overlays for
single counties in all cases.

Generally the procedure for producing tract/BNA maps is to enter the TIGER
data for the county of interest and all the STF1A files for the same county
by selecting the appropriate options from the data entry menus.


                                                                     163
Usually a new DOS directory will be set up for each map area. It must be on
the same disk as the \OZGIS directory.

Census data is often not exactly what is required, PREPARE DATA FOR DISPLAY
will probably be used to produce derived attributes. Common processing is to
amalgamate age ranges and to normalise by dividing by total population.

The boundary line segments will probably be thinned to reduce
their size and speed up display by using the PREPARE DATA FOR DISPLAY option.

The BUILD TOPOLOGY option has to be used to form the polygons from the
TIGER lines data.

Finally the data are mapped with SIMPLE CENSUS-TYPE mapping of INTERACTIVE
DISPLAY AND ANALYSIS options.

The most important sections in this appendix are:

Processing STF1A data  and
OzGIS Processing of TIGER data

These sections follow, with an example and further more general information
after that.

  B. 2 Documentation
      -------------

Extensive documentation is available from the Census Bureau and on the
CD-ROMs.

Some of that documentation is reproduced here.

  B. 3 OzGIS Processing of TIGER data
      ------------------------------

You enter TIGER data into OzGIS with the data entry process.

Select IMPORT GEOGRAPHIC FILES from the top menu and then
IMPORT A TIGER FORMAT GEOGRAPHIC FILE

The next menu is:

TRACTS / BNA
BLOCK GROUPS
BLOCKS
ZIP CODES (IF PRESENT)
VOTING DISTRICTS
SELECT LANDMARKS BY FEATURE CODES
SELECT LINES BY FEATURE CODES
SELECT POINTS BY FEATURE CODES

You will probably use options TRACTS / BNA and BLOCK GROUPS to extract
boundaries for mapping with STF1A data. The build process has to be used
to build the polygons.

The option SELECT LINES BY FEATURE CODES will also be used often to extract
line overlay data such as roads.


                                                                     164
The Feature codes are described later in this appendix.

The TIGER files must be present on hard disk or CD-ROM  with file names in a
restricted form.

It seems that each state is on at least one CD-ROM (some states like California
are on two or more, but most are either on one by themselves or share
a disk with one or two small states). The structure of the CD-ROM appears
to be: general documentation and full state FIPS listing files at
the top  (GRF_N_xx, where xx is the state's FIPS code); a subdirectory
for each state named by its FIPS code (e.g. Indiana's subdirectory is 18); in
each state's subdir are subdirectories for each county, again by FIPS codes
(e.g. Allen County, Indiana is 003) using 3 digits; in each of these reside the
(finally!) Tiger files of the form TGRXXYYY.F4n, where XX is the STATE code and
YYY is the county code and n is the record format code.

You usually read data directly off CD-ROM by giving the full file name.
The files will probably already be named correctly on CD-ROM, where they usually
to have extensions of the form ".F4n". e.g. e:/36/121/tgr36121.f41
You give the name of any one of the files and that name is used as a
template for the rest of the files.

There are two forms of file name:

Firstly, as files are often on CD-ROM with file names of the form, for
example boondocks.f41, boondocks.f42, boondocks.f43 etc, the data entry
process will look for sets of files with names of the form ????.f4n

If no files are present of this form it will look for a second form, where
the file names must contain the string "TGRn" where n is 1,2,3 or 7. This
ensures that related files are named as a set. Files on hard disk are usually
given names with extension ".DAT".

Name examples on hard disk are WASHTGR1.DAT, WASHTGR2.DAT, WASHTGR3.DAT,
WASHTGR7.DAT and  TGR1NY.DAT and TGR2NY.DAT

Only the files of the required types are required:

Extracting Census boundaries usually requires types 1 and 2, but in some
cases the zone names (e.g. voting districts or 1980 regions) require that
the record type 3 file is also processed.

Extracting lines by feature code requires types 1 and 2.

Extracting points by feature codes requires type 1.
Extracting landmark features by feature code requires type 7.

Address extraction by feature code requires types 1 and 2. Type 6 records
are not processed.

  B. 4 Processing STF1A data
      ---------------------

US Census data STF1A files can be entered into the system with the entry
process by choosing IMPORT ATTRIBUTE FILES from the menu and then
one of:
IMPORT USA CENSUS STF 1A FILES FOR TRACT/BNA
IMPORT USA CENSUS STF 1A FILES FOR BLOCK GROUPS

                                                                     165

The data files must be present with names of the form *1An* where n is in
the range 0 to 9. The supplied files on CD-ROM will probably have extensions
DBF and file names in the correct form. Data files on hard disk are usually
given the extension .DAT

Example file names are e:/xyz/stf1a0dc.dbf, stf1a0in.dat, wash1a3.dat
You do not need to give the file extension if it is the default .DAT

All files present will be processed, so anywhere between 1 and 10 files
will be read. It takes a long time to read all the data, but it will be
usual to load it all in once.

You give the name of any one of the files and that name is used as a
template for the rest of the file names.

If you only want to process one or two files you will have to copy them to hard
disk. It will be usual to input files directly from CD-ROM as they can be very
big. The internal files are much smaller as only a small part of the data is
required.

THE FIRST STF1A FILE (number zero) MUST ALWAYS BE PRESENT as it contains the
level codes necessary to avoid multiple records being extracted.

A parameter file must be given. These are described in the next section.
You can use the supplied parameter file by giving the name as *STF1A, as
described in the following section.

You can also set up your own parameter file, probably by modifying the example
provided.

Attributes (table variables) that are not on the parameter file will not be
processed, so a subset can be extracted by including just the appropriate
entries in the file.

You give a list of numbers for the counties you want to process e.g.
001, 005,...

If all the values for an attribute are zero nothing is written to the output
file for that attribute.

A log file is output to OZGIS.OUT which lists the attributes output and the
position on the file. The positions are of value when generating new
attributes as arithmetic expressions and for selecting attributes for display.

  B. 5 The STF1A parameter file
      ------------------------

A parameter file must be used to define the description, units and number of
decimal places for each variable (field).

A sample parameter file is provided:   \OZGIS\STF1A.PRM (i.e. called *STF1A)

This file was generated by editing the STF1A data dictionary, and there is no
guarantee that it is correct. (We would be pleased to accept a better version).

The format is fixed, so ensure any file has data in the correct columns if you
modify the file. The first line of the file is a comment, then there is one

                                                                     166
line for each Census table variable that is to be processed in the following
format:

 8 characters table name
 2 characters filler
30 characters variable description
 2 characters filler
10 characters units description
 2 characters filler
 1 digit number of decimal places (0 or 2)


The example parameter file is as follows:

Sample STF1A parameter file
P0010001  TOTAL  PERSONS                  PERSONS     0
P0020001  TOTAL  FAMILIES                 FAMILIES    0
P0030001  TOTAL HOUSEHOLDS                HOUSEHOLDS  0
P0040001  PERSONS INSIDE URBANIZED AREA   PERSONS     0
P0040002  PERSONS OUTSIDE URBANIZED AREA  PERSONS     0
             .
             .
             .
             .
             .

  B. 6 Example
      -------

You should have looked at the early chapters on entering data and displaying
Census-type maps before you look at this example.


Suppose you want to produce a map of 1990 Census data for three counties in
Texas for tract/BNA zones.

First you look up the county FIPS codes in the documentation:

48         Texas
     .
     .
48   047   Brooks County
     .
     .
48   117   Deaf Smith County
     .
     .
48   301   Loving County

So the codes are 047, 117 and 301.


Now set up a directory to work in on the SAME disk as the \OZGIS directory.

e.g.
CD \
MKDIR TEXAS
CD TEXAS

                                                                     167


Now get the CD-ROM with the STF1A file for Texas and the TIGER CD-ROMs for
the three counties.

What you need to do is to prepare an attribute file with Census data for
the three counties and three geographic files, one for each county.


You will probably find it most profitable to work through this example
using your own CD-ROM files.



Step1: input the Census data
----------------------------

Mount the STF1A CD-ROM in the drive. Suppose the files are called
TEXAS1A0.DBF ......... TEXAS1A9.DBF.

Select IMPORT DATA FILES from the top menu.

A menu appears:

TUTORIALS & SYSTEM INFORMATION
IMPORT GEOGRAPHIC FILES
IMPORT ATTRIBUTE FILES
IMPORT A NAMES FILE
IMPORT A COMBINE FILE
IMPORT A DEVICE FILE
IMPORT A MARKER FILE

select the option to IMPORT ATTRIBUTE FILES

A new menu appears:

IMPORT A STANDARD FORMAT ATTRIBUTE FILE
IMPORT A SPREADSHEET WK1 FORMAT FILE
IMPORT A DATABASE (SIMPLE) FORMAT ATTRIBUTE FILE
IMPORT A LAMM FORMAT ATTRIBUTE FILE
IMPORT USA CENSUS STF 1A FILES FOR TRACT/BNA
IMPORT USA CENSUS STF 1A FILES FOR BLOCK GROUPS
IMPORT ATLAS DATA FILES

Obviously you now select:

IMPORT USA CENSUS STF 1A FILES FOR TRACT/BNA

Give the input data file as E:/xxx/TEXAS1A0.DBF (using the correct drive)

Give the output attribute file as TEXAS1 (no extension!!)

Give the parameter file as *STF1A

Give the numbers for the counties i.e. 047, 117 and 301.

All the files will be processed. Trace messages will say what is going on.


                                                                     168
Exit from the program.

Either print the file OZGIS.OUT or copy it to a file. This is a list of
the census variables and their positions in the attribute file.


Some comments ....... the file name given (TEXAS1A0.DBF) is used as a template
to generate the other file names (TEXAS1A1.DBF etc) and all files in the set
on the CD-ROM are processed.

If the file name is not of the standard form you have to copy the files to
hard disk and rename them.

You can process just some of the files by copying them to hard disk (the first
file, number zero, must always be there). i.e. all the files present are
processed.


Step2: derive census variables (optional)
-----------------------------------------

You now have an attribute file called TEXAS1 ready for mapping. However,
raw Census variables are often not exactly what you want.

Suppose you actually want to map teenagers in the age group 12 to 15 years old.

Also, if you are interested in the way the data are spatially distributed you
have to normalise the data to allow for differences in the total number of
people in the different tract/BNAs.

This can be done as follows:

First look at the file OZGIS.OUT from the data entry process to find the
variable numbers. Suppose it looks like:

  1  TOTAL  PERSONS
    .
    .
    .
108  12 AND 13 YEARS
109  14 YEARS
110  15 YEARS
    .
    .
    .

The new variable is the sum of the three age variables, divided by the total.


Now select PREPARE DATA FOR DISPLAY from the top menu.

The menu looks like:

PROCESS ATTRIBUTE FILES
PROCESS GEOGRAPHIC FILES
PROCESS NAMES FILES
OUTPUT EXTERNAL DATA FILES


                                                                     169

Select PROCESS ATTRIBUTE FILES, which gives another menu:

FORM ATTRIBUTES WITH ARITHMETIC EXPRESSIONS
AMALGAMATE ATTRIBUTE DATA FOR AN COMBINE FILE


Select FORM ATTRIBUTES WITH ARITHMETIC EXPRESSIONS


Now you have to specify an input attribute file, which is here TEXAS1, and a
new output file, say TEXAS2

You can then define a series of arithmetic operations (type H for help)

So you give the arithmetic expression as:

(#108+#109+#110) / #1 * 100.0

You also have to give a description, say "12 TO 15 YEAR OLDS" and a
units description, say "%POP".

Type an expression "E" to exit.



Step 3: Enter the TIGER data
----------------------------

You will have a CD-ROM for each County. Put the first in the drive.

Suppose the files for Brooks County have names tgr48047.d41, tgr48047.f42 etc

Select IMPORT DATA FILES from the top menu.

select IMPORT GEOGRAPHIC FILES and then IMPORT A TIGER FORMAT GEOGRAPHIC FILE.

The TIGER menu is:

TRACTS / BNA
BLOCK GROUPS
BLOCKS
ZIP CODES (IF PRESENT)
VOTING DISTRICTS
SELECT LANDMARKS BY FEATURE CODES
SELECT LINES BY FEATURE CODES
SELECT POINTS BY FEATURE CODES

Obviously, you need to select TRACTS / BNA as that is what you extracted
Census data for.

As before, give the input data as the name of one of the CD-ROM files, say
D:/48/047/TGR48047.F42, and the new geographic file as say BROOKS1

If there are problems reading the files you may have to copy the ones required
to hard disk and rename them, as described in previous sections.

The file BROOKS1 contains the lines that form the boundaries of the tract/BNAs.

                                                                     170

Suppose you also would like to display a lines overlay on your map of important
roads.

Looking at the section on feature codes you find that a range of 110 to 128
covers primary and secondary roads.

So, select SELECT LINES BY FEATURE CODES

Give the input data file as before, and the output geographic file as
say BROOKRD

Give the feature code range as found: 110 to 128


Repeat the process for the TIGER files for each of the counties so you
end up with a geographic file of boundaries for tract/BNAs for each county,
and line overlay files for the roads.



Step4: Simplify lines
---------------------

Often you will want to thin the lines data i.e. throw away a lot of the points.

You do this for several reasons:

.  The less the number of vertices the faster map display is.

.  You often dont care if the map is particularly accurate, its the attribute
data you are interested in.

.  Your screen is low resolution, there is no advantage in having many vertices
for each pixel on the monitor.

.  When you form polygons from the lines the number of vertices in some
polygons may exceed system limits.

.  Geographic files take less disk space after thinning.

Simplification is an option in the data preparation process which reads a
geographic file and outputs a new one where the line segments have less points.

So, select PREPARE DATA FOR DISPLAY from the top menu.

Select PROCESS GEOGRAPHIC FILES and then select SIMPLIFY (THIN) LINE SEGMENTS


Give the input file as BROOKS1 and the new output file as BROOKS2.

The resolution for thinning is given as the number of pixels. For example,
if you are displaying maps on a standard VGA at 640 X 480 you might give
the resolution as 450 pixels. If you are more interested in speed of
display than appearance give a value of 100.

Repeat for the other files.


                                                                     171

Step5: Form polygons from lines
-------------------------------

The geographic files of tract/BNAs contain the line segments that form the
boundaries of the Census regions.

You have to form the zone / polygon / line structure by joining the ends of
the lines to form polygons, finding which polygons form the zones and
working out which polygons are inside others.



Select BUILD ZONES FROM LINE SEGMENTS INTO NEW GEOGRAPHIC FILE

Give the input geographic file as BROOKS2

Give the output geographic file as BROOKS

The program will now build the polygons etc.

Repeat for the other tract/BNA boundary files (not the roads!)


If you type "DIR BROO*.GEO" you will find that you have the three geographic
files created during processing:

BROOKS.GEO
BROOKS1.GEO
BROOKS2.GEO

You only need the final one, so you can delete BROOKS1.GEO and BROOKS2.GEO




Step6: Display simple maps
--------------------------

You can start by displaying some simple maps with SIMPLE CENSUS-TYPE MAPPING.

The first menu appears:

1 TUTORIALS & SYSTEM INFORMATION
2 DISPLAY A NEW MAP


choose the option to "DISPLAY A NEW MAP".

give your attribute file name i.e. TEXAS1

and give your final geographic file name i.e. BROOKS

The data are now processed, the map is displayed, and the next menu appears.

You now have a default map with legend and distribution diagram. The legend
has the numbers of zones in each class on the left and the class value ranges
to the right of the coloured boxes.

                                                                     172

If you use an option such as changing the displayed attribute you may have

Refer to the chapter at the front of the manual on using Census mapping if you
have not already looked at the example there.





Step7: Display complex maps
---------------------------

Lets display a map with the three counties tract/BNA geographic files, called
say BROOKS, DEAF and LOVING. The raw attribute file TEXAS1 will be used and
the three road overlay files BROOKSRD, DEAFRD and LOVINGRD will be used.

Type OZGIS to execute the main mapping program.

the first menu enables you to select the type of map or diagram that is
required:

DISPLAY ZONES FOR AN ATTRIBUTE FILE
DISPLAY LINES FOR AN ATTRIBUTE FILE
DISPLAY SITES FOR AN ATTRIBUTE FILE
DISPLAY BIVARIATE ZONES FOR TWO ATTRIBUTE FILES
DISPLAY ZONES & LINES FOR TWO ATTRIBUTE FILES
DISPLAY ZONES AND SITES FOR TWO ATTRIBUTE FILES
DISPLAY GEOGRAPHIC FILES (NO ATTRIBUTES)
DISPLAY ATTRIBUTE FILES (DIAGRAMS)
DISPLAY A SAVED-DISPLAY FILE
DISPLAY A PRESENTATION FILE

Select DISPLAY ZONES FOR AN ATTRIBUTE FILE for a straight forward
choropleth map.

Give the attribute file as TEXAS1 and give one of the geographic boundary
files, say BROOKS.

A map will be displayed that will be the same as that with the Census mapping
process. The  difference is that you now have many more options for mapping.

The main mapping menu will now appear on the toolbar:

Attributes
Class
Features
Overlays
Regions
Analyse
Save

First we will add the other two tract/BNA files to the map. This requires
an understanding of map regions which are defined by both a geographic
window and the part of the screen it is to appear on.

select MAP REGIONS.


                                                                     173
A menu then appears of the following form:

CHANGE THE DISPLAYED ITEMS IN THE MAP
CHANGE MAP REGION WINDOW (GEOGRAPHIC AREA)
ZOOM MAP REGION WINDOW ABOUT X-HAIR POINT
CHANGE MAP REGION VIEWPORT (SCREEN AREA)
DEFINE NEW REGION FOR QUANTISED ZONES
DISPLAY MORE QUANTISED ZONES ON A REGION
DELETE QUANTISED ZONES FROM REGION

What you do next depends on whether the counties are adjacent or not.

If counties are adjacent, add the files to the existing map region as
follows:

select ZOOM MAP REGION WINDOW ABOUT X-HAIR POINT, choose a location with
the cursor and mouse or arrows (select with left button or Enter). Give
a zoom factor, say 4.

You now have space for the other counties. Select DISPLAY MORE QUANTISED ZONES
ON A REGION and give the next boundary geographic file DEAF. Repeat for LOVING.

If the counties are not adjacent you probably want to display the files in
different parts of the screen in their own regions. Use the option
DEFINE NEW REGION FOR QUANTISED ZONES to do this.

You probably end up with a mess. Use CHANGE MAP REGION WINDOW (GEOGRAPHIC AREA)
and CHANGE MAP REGION VIEWPORT (SCREEN AREA) to clean up the map layout.

You often find that Census maps have very small polygons in the centres of
cities. You can add "blow-ups" of the CBDs by using DEFINE NEW REGION FOR
QUANTISED ZONES to add a geographic file a second time to the map and then
use CHANGE MAP REGION WINDOW (GEOGRAPHIC AREA) to display just the desired
area. (you can also use data preparation options to subset for complete polygons

Finally add the roads. Type ESC to go back to the main map menu and
select DEFINE GEOGRAPHIC OVERLAYS

A menu appears that offers options for several types of overlays:

OVERLAY LINE SEGMENTS FROM A GEOGRAPHIC FILE
OVERLAY MARKERS FOR SITES IN GEOGRAPHIC FILE
OVERLAY NAMES FOR SITES IN GEOGRAPHIC FILE
UNDERLAY POLYGONS FROM GEOGRAPHIC FILE
OVERLAY LINE SEGMENTS FOR FEATURE CODES
OVERLAY MARKERS FOR SITES FOR FEATURE CODES
OVERLAY NAMES FOR SITES FOR FEATURE CODES
UNDERLAY POLYGONS FOR FEATURE CODES

Use OVERLAY LINE SEGMENTS FROM A GEOGRAPHIC FILE to overlay the road geographic
files BROOKSRD, DEAFRD and LOVINGRD one at a time. If you have more than one
region you will have to give the region number - the number is defined by the
order the regions were defined. You could also use OVERLAY LINE SEGMENTS FOR
FEATURE CODES and give a feature code range to subset the lines further.

You can add the names of the tract/BNAs to the map by using OVERLAY NAMES FOR
SITES IN GEOGRAPHIC FILE and adding each of the boundary files.


                                                                     174
Having spent all this time you dont want to lose the map, so save it with the
option SAVE DISPLAY FEATURES from the main map menu.


The other options are all described fully elsewhere in the manual.



                                                                     175

  B. 7 OzGIS Census Zone Names
      -----------------------

Federal Information Processing Standards (FIPS) codes are assigned
for a variety of geographic entities, including American Indian and
Alaska Native area, congressional district, county, county subdivision,
metropolitan area, place, and State. The structure, format, and meaning
of FIPS codes used in the census are shown in the 1990 census
Geographic Identification Code Scheme; in the data dictionary portion of
the technical documentation for summary tape files, CD-ROM's, and
microfiche.

The names assigned to Census polygons in OzGIS are generated from the
standard codes.

Tract / BNA name = 3digit county + 5 digit tract FIPS code

Block group name = 3digit county + 5 digit tract FIPS code + first block digit

If you want to input your own data try generating a template attribute data
file with the data preparation options.

These names are unique only within a state.

  B. 8 STF1A Census data
      -----------------

Summary Tape File 1 (STF 1) contains 100-percent data.  Population items
include age, race, sex, marital status, Hispanic origin, household type,
and household relationship.  Population items are cross tabulated by age,
race, Hispanic origin, or sex.  Housing items include occupancy/vacancy
status, tenure, units in structure, contract rent, meals included in
rent, value, and number of rooms in housing unit.  Housing data are cross
tabulated by race or Hispanic origin of householder or by tenure.

Selected aggregates and medians also are provided.  Data are presented in
37 population tables (matrices) and 63 housing tables (matrices).

  B. 9 STF1A Geographic areas
      ----------------------


  B. 9. 1 Blocks
          ------

Census blocks are small areas bounded on all sides by visible features such
as streets, roads, streams, and railroad tracks, and by invisible
boundaries such as city, town, township, and county limits, property lines,
and short, imaginary extensions of streets and roads.

  Tabulation blocks, used in census data products, are in most cases the
same as collection blocks, used in the census enumeration. In some
cases, collection blocks have been "split" into two or more parts
required for data tabulations. Tabulation blocks do not cross the
boundaries of counties, county subdivisions, places, census tracts or
block numbering areas, American Indian and Alaska Native areas,

                                                                     176
congressional districts, voting districts, urban or rural areas, or
urbanized areas. The 1990 census is the first for which the entire
United States and its possessions are block-numbered.

  Blocks are numbered uniquely within each census tract or BNA. A block
is identified by a three-digit number, sometimes with a single
alphabetical suffix. Block numbers with suffixes generally represent
collection blocks that were "split" in order to identify separate
geographic entities that divide the original block. For example, when a
city limit runs through data collection block 101, the data for the
portion inside the city is tabulated in block 101A and the portion
outside, in block 101B. A block number with the suffix "Z"
represents a "crews-of-vessels" entity for which the Census
Bureau tabulates data, but that does not represent a true geographic
area; such a block is shown on census maps associated with an anchor
symbol and a census tract or block numbering area with a .99 suffix.

  B. 9. 2 Block Groups
          ------------

A geographic block group (BG) is a cluster of blocks having the same
first digit of their three-digit identifying numbers within a census
tract or block numbering area (BNA). For example, BG 3 within a census
tract or BNA includes all blocks numbered between 301 and 397. In most
cases, the numbering involves substantially fewer than 97 blocks.
Geographic BG's never cross census tract or BNA boundaries, but may
cross the boundaries of county subdivisions, places, American Indian
and Alaska Native areas, urbanized areas, voting districts, and
congressional districts. BG's generally contain between 250 and 550
housing units, with the ideal size being 400 housing units.

  B. 9. 3 Census tract and block numbering area
          -------------------------------------

Block Numbering Area (BNA)

Block numbering areas (BNA's) are small statistical subdivisions of
a county for grouping and numbering blocks in nonmetropolitan counties
where local census statistical areas committees have not established
census tracts. State agencies and the Census Bureau delineated BNA's
for the 1990 census, using guidelines similar to those for the
delineation of census tracts. BNA's do not cross county boundaries.

  BNA's are identified by a four-digit basic number and may have a
two-digit suffix; for example, 9901.07. The decimal point separating
the four-digit basic BNA number from the two-digit suffix is shown in
printed reports, in microfiche, and on census maps; in machine-readable
files, the decimal point is implied. Many BNA's do not have a suffix;
in such cases, the suffix field is left blank in all data products. BNA
numbers range from 9501 through 9989.99, and are unique within a county
(numbers in the range of 0001 through 9499.99 denote a census tract).
The suffix .99 identifies a BNA that was populated entirely by persons
aboard one or more civilian or military ships. A "crews-of-vessels" BNA
appears on census maps only as an anchor symbol with its BNA number (and
block numbers on maps showing block numbers); the BNA relates to the ships
associated with the onshore BNA's having the same four-digit basic number.
Suffixes in the range .80 through .98 usually identify BNA's that either
were revised or were created during the 1990 census data collection

                                                                     177
activities. Some of these revisions produced BNA's that have extremely
small land area and ay have little or no population or housing. For data
analysis, such a BNA can be summarized with an adjacent BNA.

  B. 9. 4 Census Tract
          ------------

Census tracts are small, relatively permanent statistical subdivisions of a
county. Census tracts are delineated for all metropolitan areas (MA's) and
other densely populated counties by local census statistical areas
committees following Census Bureau guidelines (more than 3,000 census
tracts have been established in 221 counties outside MA's). Six States
(California, Connecticut, Delaware, Hawaii, New Jersey, and Rhode Island)
and the District of Columbia are covered entirely by census tracts. Census
tracts usually have between 2,500 and 8,000 persons and, when first
delineated, are designed to be homogeneous with respect to population
characteristics, economic status, and living conditions. Census tracts do
not cross county boundaries. The spatial size of census tracts varies
widely depending on the density of settlement. Census tract boundaries are
delineated with the intention of being maintained over a long time so that
statistical comparisons can be made from census to census. However,
physical changes in street patterns caused by highway construction, new
development, etc., may require occasional revisions; census tracts
occasionally are split due to large population growth, or combined as a
result of substantial population decline. Census tracts are referred to
as "tracts" in all 1990 data products.

  Census tracts are identified by a four-digit basic number and may have
a two-digit suffix; for example, 6059.02. The decimal point separating
the four-digit basic tract number from the two-digit suffix is shown in
printed reports, in microfiche, and on census maps; in machine-readable
files, the decimal point is implied. Many census tracts do not have a
suffix; in such cases, the suffix field is left blank in all data
products. Leading zeros in a census tract number (for example, 002502)
are shown only on machine-readable files.

  Census tract numbers range from 0001 through 9499.99 and are unique
within a county (numbers in the range of 9501 through 9989.99 denote a
block numbering area). The suffix .99 identifies a census tract that
was populated entirely by persons aboard one or more civilian or
military ships. A "crews-of-vessels" census tract appears on
census maps only as an anchor symbol with its census tract number (and
block numbers on maps showing block numbers). These census tracts
relate to the ships associated with the on-shore census tract having
the same four-digit basic number. Suffixes in the range .80 through .98
usually identify census tracts that either were revised or were created
during the 1990 census data collection activities. Some of these
revisions may have resulted in census tracts that have extremely small
land area and may have little or no population or housing. For data
analysis, such a census tract can be summarized with an adjacent census
tract.

  B. 9. 5 County
          ------

The primary political divisions of most States are termed "counties." In
Louisiana, these divisions are known as "parishes." In Alaska, which has no
counties, the county equivalents are the organized "boroughs" and the

                                                                     178
"census areas" that are delineated for statistical purposes by the State of
Alaska and the Census Bureau. In four States (Maryland, Missouri, Nevada,
and Virginia), there are one or more cities that are independent of any
county organization and thus constitute primary divisions of their States.
These cities are known as "independent cities" and are treated as
equivalent to counties for statistical purposes. That part of Yellowstone
National Park in Montana is treated as a county equivalent. The District of
Columbia has no primary divisions, and the entire area is considered
equivalent to a county for statistical purposes.

  Each county and county equivalent is assigned a three-digit FIPS code
that is unique within State. These codes are assigned in alphabetical
order of county or county equivalent within State, except for the
independent cities, which follow the listing of counties.

  B. 9. 6 Hierarchical Presentation
          -------------------------

A hierarchical geographic presentation shows the geographic entities
in a superior/subordinate structure in census products. This structure
is derived from the legal, administrative, or areal relationships of
the entities. The hierarchical structure is depicted in report tables
by means of indentation, and is explained for machine-readable media in
the discussion of file structure in the geographic coverage portion of
the abstract in the technical documentation. An example of hierarchical
presentation is the "standard census geographic hierarchy":  block, within
block group, within census tract or block numbering area, within place,
within county subdivision, within county, within State, within division,
within region, within the United States. Graphically, this is shown as:

 United States
   Region
     Division
      State
         County
           County subdivision
            Place (or part)
               Census tract/block numbering area (or part)
                Block group (or part)
                   Block

  B. 9. 7 Zip codes
          ---------

ZIP Codes are administrative units established by the United States
Postal Service (USPS) for the distribution of mail. ZIP Codes serve
addresses for the most efficient delivery of mail, and therefore
generally do not respect political or census statistical area
boundaries. ZIP Codes usually do not have clearly identifiable
boundaries, often serve a continually changing area, are changed
periodically to meet postal requirements, and do not cover all the land
area of the United States. ZIP Codes are identified by five-digit codes
assigned by the USPS. The first three digits identify a major city or
sectional distribution center, and the last two digits generally
signify a specific post office's delivery area or point. For the 1990
census, ZIP Code data are tabulated for the five-digit codes in STF 3B.

                                                                     179

  B.10 The STF1A file
      --------------


  B.10. 1 File Segments
          -------------

The file is segmented into 10 dBase III (.DBF) files, designated
STF1A0ss.DBF through STF1A9ss.DBF where ss is the two-character State
abbreviation.  The STF1A0 segment contains the full 67 field identification
section.  The identification field names are shown in the Data Dictionary
chapter of the technical documentation.  Segments STF1A1 through STF1A9
each contain seven identification fields repeated from the STF1A0 segment.
They are shown below.

Identification Fields Common To All Segments

         SUMLEV                    Summary Level
         STATEFP                   State (FIPS)
         CNTY                      County (FIPS)
         COUSUBFP                  County Subdivision (FIPS)
         PLACEFP                   Place (FIPS)
         TRACTBNA                  Census Tract/Block Numbering Area
         BLCKGR                    Block Group
         LOGRECNU                  Logical Record Number

The segments are divided as shown below.  Tables 12 and 13 go across
segments.

Data Tables In Each Segment

         STF1A0                    P1 - P10
         STF1A1                    P11 - P12(pt.2)
         STF1A2                    P12(pt. 3) - P12(pt. 5)
         STF1A3                    P12(pt. 6) - P12(pt. 8)
         STF1A4                    P12(pt. 9) - P13(pt. 1)
         STF1A5                    P13(pt. 2) - P19
         STF1A6                    P20 - P35
         STF1A7                    P36, H1 - H20
         STF1A8                    H21 - H40
         STF1A9                    H41 - H55

Parts of Table P12

(Each part contains 31 categories of age)

         Part 1                    White males
         Part 2                    White females
         Part 3                    Black males
         Part 4                    Black females
         Part 5                    American Indian, Eskimo or Aleut males
         Part 6                    American Indian, Eskimo or Aleut females
         Part 7                    Asian or Pacific Islander males
         Part 8                    Asian or Pacific Islander females
         Part 9                    Other race males
         Part 10                    Other race females

                                                                     180

Parts of Table P13

(Each part contains 31 categories of age)

         Part 1                    Hispanic origin males
         Part 2                    Hispanic origin females

You can process all or some of the files.

  B.10. 2 Field Names In Numeric Data Tables
          ----------------------------------

Fields in numeric data tables are named according to a convention which
identifies the tables and the sequence of the data item within the table.
The 310 data items in P12, for example, are identified as P0120001 through
P0120310.  The one data item in table H23A is identified as H023A001.

Components Of The Field Name

Character 1                    P or H
Character 2-4                  Table number; right justified with
                               leading zeroes
Character 5                    Sub-table letter; zero if not applicable
Character 6-8                  Item number; right justified with
                               leading zeroes

  B.11  TIGER US Census Digital Map Data
      ---------------------------------

The 1990 Census TIGER/Line file provides digital data for all 1990 census
map features and boundaries, the associated 1990 census final tabulation
geographic area codes (such as 1990 census block numbers), and the codes
for the January 1, 1990 legal and statistical areas on both sides of each
line segment of every mapped feature.  This version also contains the final
voting district codes and the 1990 census designated place codes.

The 1990 Census TIGER/Line files cover the entire United States, Puerto
Rico, the Virgin Islands of the United States, American Samoa, Guam, the
Northern Mariana Islands, Palau, the other Pacific entities that were part
of the Trust Territory of the United States for the 1980 census (the
Marshall Islands and the Federated States of Micronesia), and the Midway
Islands (to provide complete mapping within the boundaries of the State of
Hawaii).

  B.12  TIGER files
      ------------

The normal geographic coverage for a 1990 Census TIGER/Line file is a
county.  The files can be combined to cover the whole Nation and its
possessions.  Each 1990 Census TIGER/Line file consists of 12 record types
that collectively contain geographic information (attributes) such as
address ranges and ZIP codes for street segments (only in areas covered by
the 1980 GBF/DIME-Files), names and codes of feature types, codes for legal
and statistical entities, selected 1980 census geographic area codes,
latitude/longitude coordinates of linear and point features, landmark
features, area landmarks, and area and polygon boundaries.  The 12 record
types are on the tape as 12 separate files.

                                                                     181


The 1990 Census TIGER/Line file contains basic information for 1990 census
geographic area codes, basic map features and their names, and address
ranges in the form of 12 "Record Types."  The record types are as follows:

     1.     Basic Data Records (Individual Feature Segment Records)
     2.     Shape Coordinate Points (Feature Shape Records)
     3.     Additional Decennial Census Geographic Area Codes
     4.     Index to Alternate Feature Names
     5.     Feature Name List
     6.     Additional Address Range and ZIP Code(2) Information
     7.     Landmark Features
     8.     Area Landmarks
     A.     Additional Polygon Geographic Area Codes
     I.     Area Boundaries
     P.     Polygon Location
     R.     Record Number Range

Each segment record contains appropriate decennial census and, when
appropriate, FIPS(1) geographic area codes, latitude/longitude coordinates
for all line segments and point features, the name of the feature
(including the relevant census feature class code identifying the segment
by category), and, for areas formerly covered by the GBF/DIME-Files, the
address ranges and the ZIP Code associated with those address ranges for
each side of street segments.  For other areas, the TIGER/Line files do not
contain address ranges or ZIP Codes.  The shape records provide coordinate
values that describe the shape of those feature segments that are not
straight.

Record types 1,2,3 and 7 are processed by OzGIS. The types used depend on
the options chosen:

Record Type 1:    Basic Data Record

Record Type 1 provides a single record for each unique line segment in the
1990 Census TIGER/Line file.  The end points of the line segments are
expressed in latitude/longitude coordinate values in degrees and decimal
fractions of a degree to six decimal places.  This record also contains
address ranges and ZIP codes (in selected areas) and geographic area codes
for each side of the line segment.  By convention, if one is standing at
the "from" coordinate position facing the "to" coordinate position,
data listed in the fields carrying a right qualifier would indeed be found
to the right of the line segment.  Data users can collect the necessary
segments to construct polygons and features that intersect from the
information contained in this basic record.

Record Type 2:   Shape Coordinate Points

Record Type 2 provides an additional series of latitude and longitude
coordinate values that describe the shape of each line segment that is not
straight for the associated Record Type 1.  All coordinate values are
expressed in degrees and decimal fractions of a degree of latitude and
longitude.  The decimals are carried to six places to permit the
representation of lines that are very close to one another.  If the segment
in Record Type 1 is a straight line, there will not be a Record Type 2.

Record Type 3:   Additional Decennial Census Geographic Area Codes

                                                                     182

Record Type 3 includes the 1990 voting district codes provided to the
Census Bureau for the 1990 Census Redistricting Data Program.  Record Type
3 also includes some 1980 census geographic area codes and 1990 census
geographic area codes not included on Record Type 1.  The 1980 census block
numbers are available only for areas covered by the 1980 GBF/DIME-Files.
During the conversion of the 1980 GBF/DIME-Files to the TIGER data base
format, some 1980 census block numbers may have been deleted or changed.
Users are advised to check all 1980 census geographic area codes,
especially any 1980 block numbers, before using them in a planned
application.  The Census Bureau has not verified any of the 1980 census
geographic area codes in these files.  There will be discrepancies between
the geographic area boundaries and codes in these files and the 1980 census
maps, which are the basis for the 1980 census tabulations.

The TIGER/Line files may contain 1980 block numbers for portions of the
country where the Census Bureau did not tabulate 1980 census data by block
or block group.  These situations occur because these portions of the TIGER
file originated from the 1980 GBF/DIME-Files that extended beyond the 1980
block-numbered area.  Data users concerned about the validity of 1980 block
numbers are advised to discard all 1980 block numbers that do not
correspond to block numbers in the 1980 MARF or 1980 STF files.

Record Type 6:   Additional Address Range and ZIP Code Data

Record Type 6 provides additional address range information for a street
segment when the information cannot be presented as a single address range
(e.g., the house/building numbers are not uniformly arranged to form an
address range).  Additional ZIP Codes, if any, also appear in Record Type 6
for corresponding address ranges.  Record Type 6 appears only for those
counties that have address ranges and ZIP Code information in the TIGER
data base.  There is no assurance that the address ranges provided on
Record Type 6 will be "shorter" than those appearing on Record Type 1.
Data users must use Record Type 6 to obtain the complete picture of the
potential address ranges along a segment.


Record Type 7:   Landmark Features

Record Type 7 contains the area and point landmarks in the Census Bureau's
TIGER data base.  During the extraction of this data, we assigned a
temporary Landmark Identification Number that we use to link the landmark
attributes to the polygons that comprise the landmark.  If there is no
landmark in a county file, there will be no Record Type 7 or Record Type 8
for that county file.

  B.13 TIGER Geographic Area Definitions
      ---------------------------------

United States - The 50 States and the District of Columbia.

States and Statistically Equivalent Areas - The 50 States; in addition, we
treat the District of Columbia, Puerto Rico, and each of the outlying
areas-American Samoa, Guam, the Northern Mariana Islands, Palau, and the
Virgin Islands of the United States-as statistical equivalents to States
for presentation.  We also have TIGER/Line files for the Marshall Islands,
the Federated States of Micronesia, and the Midway Islands.


                                                                     183
Counties, Parishes, Statistically Equivalent Areas - The first-order
divisions of each State, the District of Columbia, Puerto Rico, and the
outlying areas:  counties for 48 States; parishes for Louisiana; boroughs
and census areas for Alaska; independent cities in Maryland, Missouri,
Nevada, and Virginia; Yellowstone National Park in Montana, "District of
Columbia" for the District of Columbia, municipios in Puerto Rico; other
entities in the outlying areas.

Minor Civil Divisions (MCDs) - Legally defined subcounty areas such as
towns and townships.  For the 1990 census, these are found in 28 States,
Puerto Rico, and the outlying areas.

Sub-MCDs - Legally defined subdivisions of a minor civil division;
specifically,  subbarrios in Puerto Rico, and municipal districts in the
Federated States of Micronesia.

Incorporated Places - Legal units incorporated as a city, town (excluding
the New England States, New York, and Wisconsin), borough (excluding Alaska
and New York), or village.

American Indian Reservations - American Indian areas with boundaries
established by treaty, statute, and/or executive or court order.

Alaska Native Regional Corporations (ANRCs) - Corporate entities
established by the Alaska Native Claims Settlement Act (P.L. 92-203) to
carry out the business and non-profit operations established by and for
Native Alaskans under the Act.  Twelve ANRCs have specific boundaries and
cover the State of Alaska except for the Annette Islands Reserve.

Statistical Areas

Alaska Native Village Statistical Areas (ANVSAs) - 1990 census statistical
areas that delineate the settled area of each Alaska Native village (ANV).
Officials of Alaska Native Regional Corporations (ANRCs) and other
appropriate State officials delineated the ANVSAs for the Census Bureau for
the sole purpose of presenting census data.

Tribal Designated Statistical Areas (TDSAs) - Geographic areas delineated
for 1990 census data tabulation purposes by tribal officials of Federally
and State-recognized tribes outside of Oklahoma that do not have a legally
defined reservation.

Tribal Jurisdiction Statistical Areas (TJSAs) - Geographic areas delineated
for 1990 census data tabulation purposes by tribal officials in Oklahoma
for Federally recognized tribes that do not have a legally defined
reservation.

Census County Divisions (CCDs) - Areas delineated by the Census Bureau in
cooperation with State and local officials in States where MCDs are not
adequate for reporting subcounty statistics.

Unorganized Territories (UTs) - Areas delineated by the Census Bureau for
those portions of a State with MCDs where MCDs do not exist or are not
adequate for reporting subcounty statistics.

Census Designated Places (CDPs) - Densely settled population centers
without legally defined corporate limits or corporate powers, defined in
cooperation with State officials and local data users.

                                                                     184

Census Tracts - Small, locally delineated statistical areas within selected
counties, generally having stable boundaries and, when first established by
local committees, designed to have relatively homogeneous demographic
characteristics.

Block Numbering Areas (BNAs) - Areas delineated by State governments or the
Census Bureau for the purpose of grouping and numbering blocks in counties
without census tracts.

Census Blocks - Small, usually compact areas, usually bounded by streets
and other prominent physical features as well as boundaries of legal areas
for which the Census Bureau tabulates data.  Blocks do not cross county,
census tract, or BNA boundaries.

Voting Districts (VTDs) - For the 1990 census, the term "voting district"
replaces the 1980 census term "election precinct."  A voting district is
any of a variety of areas (for example, election districts, precincts,
legislative districts, wards) defined by State and local governments for
purposes of elections.  The 1990 voting district codes that appear in the
1990 census version of the TIGER/Line files were supplied by the State
under the 1990 Census Redistricting Data Program.  The boundaries of the
voting districts recorded in the TIGER/Line files may represent pseudo-
voting districts; the States were required to have voting districts follow
1990 census block boundaries, and therefore they may have had to relocate
the boundaries of actual voting districts to a nearby feature used as a
block boundary.  States had the option of participating in the program on a
county-by-county basis.  Voting districts do not appear in all TIGER/Line
files.

  B.14 TIGER feature codes
      -------------------

Data can be extracted from the TIGER files and subset for display by
feature codes.

Feature codes are derived from the Census Feature Class Codes (CFCC)
by changing the leading alphabetic character by its position in the
alphabet.

This is a series of codes that provides more detailed information on the
classification of the line segment, such as class of road, class of stream,
and so forth.

A list of these codes follows.

CFCC    CLASSIFICATION A = ROAD FEATURES

100     Road, Classification Unknown or Not Elsewhere Classified
101     Road, undivided
102     Road, undivided, in tunnel
103     Road, undivided, underpassing
104     Road, undivided, rail line in center
105     Road, divided
106     Road, divided, in tunnel
107     Road, divided, underpassing
108     Road, divided, rail line in center


                                                                     185
110     Primary road, interstate highway and limited access road
111     Primary road, interstate highway and limited access road, undivided
112     Primary road, interstate highway and limited access road,
         undivided, in tunnel
113     Primary road, interstate highway and limited access road,
         undivided, underpassing
114     Primary road, interstate highway and limited  access road,
         undivided, rail line in center
115     Primary road, interstate highway and limited access road, divided
116     Primary road, interstate highway and limited access road, divided,
         in tunnel
117     Primary road, interstate highway and limited access road, divided,
         underpassing
118     Primary road, interstate highway and limited access road, divided,
         rail line in center

120     Secondary road, U.S. highway not classified 110, and state roads
121     Secondary road, U.S. highway not classified 110, and state roads,
         undivided
122     Secondary road, U.S. highway not classified 110, and state roads,
         undivided, in tunnel
123     Secondary road, U.S. highway not classified 110, and state roads,
         undivided, underpassing
124     Secondary road, U.S. highway not classified 110, and state roads,
         undivided, rail line in center
125     Secondary road, U.S. highway not classified 110, and state roads,
         divided
126     Secondary road, U.S. highway not classified 110, and state roads,
         divided, in tunnel
127     Secondary road, U.S. highway not classified 110, and state roads,
         divided, underpassing
128     Secondary road, U.S. highway not classified 110, and state roads,
         divided, rail line in center

130     Connecting road, county roads, and roads not classified as 110 or
         120
131     Connecting road, county roads, and roads not classified as 110 or
         120, undivided
132     Connecting road, county roads, and roads not classified as 110 or
         120, undivided, in tunnel
133     Connecting road, county roads, and roads not classified as 110 or
         120, undivided, underpassing
134     Connecting road, county roads, and roads not classified as 110 or
         120, undivided, rail line in center
135     Connecting road, county roads, and roads not classified as 110 or
         120, divided
136     Connecting road, county roads, and roads not classified as 110 or
         120, divided, in tunnel
137     Connecting road, county roads, and roads not classified as 110 or
         120, divided, underpassing
138     Connecting road, county roads, and roads not classified as 110 or
         120, divided, rail line in center

140     Neighborhood roads, city streets and unimproved roads
141     Neighborhood roads, city streets and unimproved roads, undivided
142     Neighborhood roads, city streets and unimproved roads, undivided,
         in tunnel
143     Neighborhood roads, city streets and unimproved roads, undivided,

                                                                     186
         underpassing
144     Neighborhood roads, city streets and unimproved roads, undivided,
         rail line in center
145     Neighborhood roads, city streets and unimproved roads, divided
146     Neighborhood roads, city streets and unimproved roads, divided, in
         tunnel
147     Neighborhood roads, city streets and unimproved roads, divided,
         underpassing
148     Neighborhood roads, city streets and unimproved roads, divided,
         rail line in center

150     Jeep trail, passable only by four-wheel drive (4WD) vehicle
151     Jeep trail, passable only by four-wheel drive (4WD) vehicle,
         undivided
152     Jeep trail, passable only by four-wheel drive (4WD) vehicle,
         undivided, in tunnel
153     Jeep trail, passable only by four-wheel drive (4WD) vehicle,
         undivided, underpassing

160     Special Road Feature
161     Cul-de-sac
162     Traffic circle
163     Cloverleaf or interchange
164     Service drive
165     Ferry crossing

170     Other Thoroughfare
171     Walkway
172     Stairway
173     Alley

NOTE:  In the portion of the TIGER/Line file prepared from the GBF/DIME-
Files, the roads are classified as Class 4 roads with a few exceptions.
The interstate highways that were identified by name as such in the
GBF/DIME-File, are classified as Class 1 roads.  Also, in the GBF/DIME-File
coverage areas, users may not find many roads with alternate names; if an
alternate name is provided, it usually represents another local name and
not a Route Number.

CFCC    CLASSIFICATION B = RAIL FEATURES

200     Railroad, Classification Unknown or Not Elsewhere Classified
201     Railroad track
202     Railroad track, in tunnel
203     Railroad track, underpassing

210     Railroad Main Track
211     Railroad main track
212     Railroad main track, in tunnel
213     Railroad main track, underpassing

220     Railroad Spur Track
221     Railroad spur track
222     Railroad spur track, in tunnel
223     Railroad spur track, underpassing

230     Railroad Yard
231     Railroad yard

                                                                     187
232     Railroad yard, in tunnel
233     Railroad yard, underpassing

240     Railroad Ferry Crossing

250     Other Rail Feature
251     Carline
252     Cog railroad, incline railway, or logging tram

CFCC    CLASSIFICATION C = PIPELINES, POWER TRANSMISSION LINES, AND
              MISCELLANEOUS TRANSPORTATION FEATURES

300     Special Transportation Feature, Classification Unknown or Not
         Elsewhere Classified

310     Pipeline

320     Power Transmission Line

330     Other Special Transportation Feature
331     Aerial tramway, monorail, or ski lift

CFCC    CLASSIFICATION D = LANDMARK FEATURES

400     Landmark Feature, Classification Unknown or Not Elsewhere
         Classified

410     Military installation

420     Multihousehold and transient quarters
421     Apartment building or complex
422     Rooming or boarding house
423     Trailer court or mobile home park
424     Marina
425     Crew of vessel
426     Housing facility for workers
427     Hotel, motel, resort, spa, YMCA, or YWCA
428     Campground
429     Shelter or mission

430     Custodial facility
431     Hospital
432     Halfway house
433     Nursing home, retirement home, or home for the aged
434     County home or poor farm
435     Orphanage
436     Jail or detention center
437     Federal penitentiary, state prison, or prison farm

440     Educational or religious institution
441     Sorority or fraternity
442     Convent or monastery
443     Educational institution
444     Religious institution

450     Transportation terminal
451     Airport or airfield
452     Train station

                                                                     188
453     Bus terminal
454     Marine terminal
455     Seaplane anchorage

460     Employment center
461     Shopping center or major retail center
462     Industrial building or industrial park
463     Office building or office park
464     Amusement center
465     Government center
466     Other employment center

470     Tower
471     Lookout tower

480     Open space
481     Golf course
482     Cemetery
483     National park or forest
484     Other federal land
485     State or local park or forest

490     Special purpose landmark
491     Post office box ZIP code

CFCC    CLASSIFICATION E = OTHER PHYSICAL FEATURES

500     Physical Feature, Classification Unknown or Not Elsewhere
         Classified

510     Fence line
520     Topographic feature
521     Ridge line
522     Mountain peak

CFCC    CLASSIFICATION F = NONVISIBLE BOUNDARIES

600     Nonvisible Boundary, Classification unknown or not Elsewhere
         Classified

610     Nonvisible Political Boundary
611     Offset corporate boundary
612     Corporate Corridor
613     Nonvisible interpolated boundary, polygon definition line for
         hydrological areas

620     Feature Extension, Not Otherwise Classified
621     Automated extension
622     Irregular block extension
623     Closure extension
624     Nonvisible separation line
625     Nonvisible corporate corridor centerline

630     Point-to-Point Line

640     Property Line

650     ZIP Code Boundary

                                                                     189

660     Map Edge

670     Statistical Boundary
671     1980 Statistical Boundary
672     1990 Block Boundary
673     1990 Statistical Boundary
674     1990 Statistical Boundary, Tabulation Areas Only

CFCC    CLASSIFICATION H = HYDROGRAPHIC FEATURES

800     Water Feature, Classification Unknown or Not Elsewhere Classified

801     Shoreline of perennial water feature
802     Shoreline of intermittent water feature

810     Stream
811     Perennial stream
812     Intermittent stream or wash
813     Braided stream

820     Canal, Ditch, or Aqueduct
821     Perennial canal, ditch, or aqueduct
822     Intermittent canal, ditch, or aqueduct

830     Lake or pond
831     Perennial lake or pond
832     Intermittent lake or pond

840     Reservoir
841     Perennial reservoir
842     Intermittent reservoir

850     Bay, Estuary, Gulf, Sound, Sea, or Ocean
851     Bay, estuary, gulf, or sound
853     Sea or ocean

860     Gravel Pit or Quarry Filled With Water

870     Nonvisible Water Area Definition Boundary
871     USGS closure line
872     Census computed center line
873     Census international water boundary, 10-mile limit, area
         measurement line
874     Census water boundary, inland or coastal or Great Lakes
875     3-mile limit water boundary

880     Special Water Feature
881     Glacier


                                                                     190
                     C. CONFIGURING OZGIS
                       =================



This appendix provides additional information about configuring OzGIS.

You should read the the information in the early chapter first as that provides
most of the information you need.



  C. 1 Hardcopy configuration for  OzMap
      ---------------------------------

This section is applicable if you want to output maps to printers or
plotters with the OzMap and Vector programs.

The configuration file \ozgis\sciplot.ini has to be set up if OzMap is going to
be used to produce hardcopy maps. The file looks like:

VGA                                  VGA or EGA
40.0      0                          HP Plotter metafile
18.0      1                          Dot-matrix printer metafile
18.0      1                          Postscript Ascii metafile
18.0      1                          Encapsulated Postscript file
18.0      0                          HPGL file
18.0      1                          CGM file
18.0      0                          WordPerfect graphics file
18.0      1 COM1                     On-line Apple Laser Writer
40.0      0 LPT1                     On-line HP plotter
00C3                                 device mode & serial modes HEXIDECIMAL

The first column is the width of the drawing surface in cm. Values will need to
be set for your plotter or printer.

The second column is the drawing line width for Postscript, Encapsulated
Postscript, Apple LaserWriter, Computer Graphics Metafile, dot matrix, and HP
LaserJet printers.
0  = Ignore parameter
1  = 1 device space units (1-10 Valid)

The third column is the port used for printers and plotters:
'COM' - Primary Serial Port
'COM2'- Secondary Serial Port
'LPT1'- Primary Parallel Port
'LPT2'- Secondary Parallel Port

The value at the bottom is a hexidecimal set of flags for setting the port for
on-line printers or plotters.

The packed coded device mode word with the device mode byte in the most
significant part of the integer, and the serial modest byte in the least
significant part of the integer.

Format of the integer = [device mode | serial modeset].


                                                                     191
Device mode byte description:  [bits]
76543210
_______0  = XON/XOFF flow control
_______1  = Hardware flow control on DSR line
______0_  = Bell with FRAME or PLTEND
______1_  = No bell with FRAME or PLTEND
_____0__  = Cr with FRAME or PLTEND
_____1__  = No cr with FRAME or PLTEND
____0___  = Check for break in PLOT
____1___  = No check for break in PLOT
___0____  = HP pen plotter handshake init
___1____  = No HP pen plotter handshake init

Serial modeset byte description:  [bits]
7      6   5  4    3        2        1    0
--Baud Rate-- -Parity-  -Stop Bits- -Char Length-
000 -   110  00 - None  0  - 1   10  - 7 Bits
001 -   300  01 - Odd   1  - 2   11  - 8 Bits
010 -   600  11 - Even
011 -  1200
100 -  2400
101 -  4800
110 -  9600
111 - 19200

For example, 9600 baud, no parity, 1 stop bit, 8 bits is

110 00 0 11 = C3 hex = 195 decimal


  C. 2 Plotter setup
      -------------


Plotter pens should agree with those defined in device files. The standard
order is:
BLACK        PEN 1
BLUE         PEN 2
GREEN        PEN 3
RED          PEN 4
YELLOW       PEN 5  The last four dont matter that much!
MAGENTA      PEN 6
CYAN         PEN 7
GREY         PEN 8

If this order conflicts with other packages in use the device files can be
modified. The order of the first four pens is particularly important for colour
simulation, although as long as all pens have different colours the final maps
will probably be acceptable.


Plotters will usually use software handshaking.

HP pen plotters require a serial interface between the  Personal Computer and
the HP pen plotter. On the PC side, a cable with a D9 or D25 connector should be
connected to a  serial port or asynchronous adapter port. On the HP pen plotter,
a cable with a D25 connector should be connected to the computer/modem port. A
detailed specification of the way the  cable should be wired follows:

                                                                     192

Serial cable wiring for HP pen plotters: 7440A, 7470A, 7475A, 7550A

 ----------------------------             -----------------------
| Personal Computer          |           | HP Pen Plotter        |
| [Serial I/O Port or        |           | [Computer/modem port] |
| Asynchronous Adapter Port] |           |                       |
 ----------------------------              ----------------------

      Transmit Data     *-------------------*   Receive Data
       [D9/Pin-3, or                             [D25/Pin-3]
        D25/Pin-2]

      Receive Data      *-------------------*   Transmit Data
       [D9/Pin-2, or                             [D25/Pin-2]
        D25/Pin-3]

      Signal Ground     *-------------------*   Signal Ground
       [D9/Pin-5, or                             [D25/Pin-7]
        D25/Pin-7]

      Data Set Ready    *-----*-------------*   Data Terminal Ready
       [D9/Pin-6, or          |                  [D25/Pin-20]
        D25/Pin-6]            |
                              |
      Clear-To-Send     *-----*
       [D9/Pin-8, or
        D25/Pin-5]

      Data Terminal Rdy *--------------*-----*  Data Set Ready
       [D9/Pin-4, or                   |         [D25/Pin-6]
        D25/Pin-20]                    |
                                       |
                                       *-----*  Clear-To-Send
                                                 [D25/Pin-5]

Please note that the previous wiring diagram is necessary if full hardware
handshake is desired. If the user intends to  use only software handshake
(XON/XOFF), then only three wires  are required. For software handshake the only
connections  required are: signal ground, receive data, and transmit data.

     There are certain restrictions when an HP pen plotter is used as the plot
device. Not all HP pen plotters possess equal capability! SciPlot only supports
the 7470A, the 7475A, and the 7550A HP Pen Plotter. There are enough control
mechanisms in SciPlot to allow the use of others though.  Please note the
following:

 The "INIT=ON" command in the VECTOR.CFG file will send initialization commands
in the I/O stream to the  plotter when VECTOR is executed. Older HP plotters
will  produce errors on receipt of these handshake mode commands.  If this
happens, set "INIT=OFF" in the VECTOR.CFG file, and the offending commands will
be deleted from the stream.



                                                                     193
                     D. GLOSSARY OF TERMS
                       =================

The purpose of this Appendix is to provide definitions for a number of
terms used within this Guide.  Most of these terms are commonly used words
or phrases which have taken on a more precise technical meaning in one of
the areas spanned by the OzGIS system.  Technical terms have been
borrowed from the jargon of statistics, data processing, computer software
and hardware, cartography, and graphic arts.  Because of the diversity of
these disciplines, it is unlikely that a potential OzGIS user will have
developed a level of expertise in each.  This glossary should provide most
of the information necessary for communicating the basic concepts of
OzGIS.

The glossary is available on-line, and is accessed by typing 'G' to a menu
selection request.

Area - 1) A measurement of the size of a geographical region whose shape is
   displayed on the OzGIS monitor.  2) An arbitrary portion of the face
   of the monitor.

Attribute - A general term for the variable associated with a set of
   geographic zones, lines or sites to be processed by OzGIS.
   Attributes may be variates, statistics or simply data collected for each
   item.  Note that the modes of display for an attribute are usually
   referred to as "single variate" or "bi-variate".  See also Variate and
   Statistic.

Background - The informationless area displayed on the monitor around a map
   and its associated components.  Usually given a user selected, neutral
   colour such as black or white.

Bit - A unit of information representing the value (either 1 or 0) of a
   single binary digit.

Bivariate - A display of the relative distribution of two different sets
   of statistics on the same map.  It must be noted that no relationship
   between the two statistics is implied by the display.  For example, if
   the distribution of little old ladies is displayed simultaneously with
   the distribution of cricket players, the result is not a display of the
   distribution of little old ladies who play cricket.  See also Variate.

Boundary - A set of lines displayed on the monitor to represent the edges
   of polygons defined to the system.  Often the same as zone edges.

Byte - A group of eight bits.  See also Bit.

Catchment - The region of influence around a site e.g. suburbs around a
   shopping centre where most of the customers live.


Character - A single symbolic pattern which may be displayed on either the
   monitor or terminal.  It may be alphabetic, numeric, or punctuational,
   as the normal symbols encountered on a typical typewriter keyboard, or a
   special symbol generated for display as an entity, such as a square root
   symbol.


                                                                     194
Choropleth Map - A map portraying the values of an attribute averaged over
   data collection units (or zones) and represented by a symbol covering
   the entire unit.  A map displayed by OzGIS represents the zones by a
   uniform colour.

Class - A convenient subdivision of the total range of values of a
   particular statistical variate.  Classes are usually chosen to make
   computations or analyses less labourious, or to make the results of such
   analyses more obvious or meaningful.  For example, the range of a set of
   values might be divided into ten equal classes in order to highlight
   items in the top ten percent.  See also Variate, Class Boundary, Class
   Interval and Class Number.

Class Boundary - The special values of variates which determine the upper
   and lower limits of the range of a class.  See also Class.

Class Interval - The range of variate values between the upper and lower
   limits of the class.  See also Class.

Class Number - A cardinal number assigned to each class into which a
   particular statistical range has been divided.  Conventionally, the
   class whose members have the lowest magnitude is assigned number 1, with
   class numbers increasing uniformly as the magnitude of class values
   increases.  See also Class.

Colour - One of the combinations of blue, green, and red which may be
   specified for display on the monitor.  The total number of colours
   available depends on the display system.

Colour Space - The range of colours which may be specified for display on
   the colour monitor.  Since the colours are specified as values of blue,
   green, and red, it is convenient to think of the colour space as a cube
   located on a standard three dimensional coordinate system.  Black is
   placed at the origin, with each of the x, y and z axes representing
   blue, green, and red, respectively.  The range of possible values is 0.0
   to 1.0 on each axis of the cube.

Continuous Colour - A method of representating statistical values
   associated with map zones by graduating zone colours to correspond with
   changes in statistical value.  From a user defined, or default, sequence
   of colours, OzGIS generates the intermediate colours to provide a
   12 colour graduated path through the colour space.  The statistic to be
   represented is quantized into 12 equal value classes, and the classes
   are assigned colours from the generated colour sequence.  This allows
   small changes in statistical value to be represented by subtle changes
   in colour, while large changes in value may be visually observed as
   significant colour differences.


Controller - A general term applied to a piece of intermediate equipment in
   the data path between the electrical signals of a processor and their
   physical realization in a peripheral device.  Within OzGIS, the term
   will most often be used for the Color Display Controller.
   It will be used to a lesser extent to describe interface controllers for
   the various disc and tape drives.

Coordinate - One of a pair of numbers which designates the location of a
   geographic point with respect to another known point.  Geographic files

                                                                     195
   for entry into the system under OzGIS must have their points
   specified in appropriately scaled and formatted coordinates.  The
   coordinates specified by the user are converted by OzGIS for display
   on the monitor.  On the monitor screen, the origin is in the lower left
   hand corner of the viewing area.  The coordinates of a point on the
   monitor screen are specified by their distance right and up from the
   origin

Crosshair Cursor - A pair of lines at right angles to each other which is
   displayed on the monitor to designate the location of a certain point of
   interest.  Under most circumstances, the location of the crosshair
   cursor may be controlled by movements of the mouse.  See also Box
   Cursor, and Joystick.

Data - Numerical values associated with certain physical phenomena, such as
   128 cm long, 14 years old, or 43 kangaroos.  As a generality,
   OzGIS was not designed to handle data, but rather the statistics
   derived from data, such as average length, medium age, or number of
   kangaroos per hectare.  See also Statistics.

Decile - One of the nine data values which divide the range of a variate
   into ten equal sized classes.  See also Quantile and Percentile.

Default - A set of parameters automatically selected by OzGIS in the
   absence of any stated preference by the user.  The actual default
   parameters may be defined by the user in the users default file.  For
   example, OzGIS may initially display a map by arbitrarily selecting
   zone colours from a palette of possible shades which the user selected
   previously.  After this default colouring, the user may wish to change
   some particular zone colour to improve the appearance of the display.

Disc - An electronic device for storing digital data on a rotating plate
   coated with magnetic material.  See also Controller.

Display - As a verb, the act of presenting information on the monitor or
   terminal for the purpose of visually communicating that information to
   the user.  This includes all the procedures necessary to correctly
   present the information in a format suitable for both the equipment and
   the viewer.  Example:  "A map is displayed on the monitor, while a menu
   is displayed on the terminal".


   As a noun, the presentation which is visually perceived when a user
   looks at the screen of the monitor or terminal;  the total information
   content on the screen.  Examples:  "The terminal display indicates the
   options possible now";  "This map display is too red".  See also Monitor
   and Terminal.

Display Elements - The components or items of a display on the OzGIS
   monitor;  for example, legend, title, image map, boundaries, image
   symbols, histograms.

Distribution - The manner in which a number of samples of data are spread
   across the range of possible values.  May be a subjective statement,
   such as:  "These data appear to have an even distribution".  More often,
   some quantifiable measure will be given such as:  "These data have a
   normal distribution with a mean of 40 and standard deviation of 3".
   Sometimes, distribution information will be presented in graphical form,

                                                                     196
   such as a histogram or scatter diagram.

Equal Value Quantization - A method of dividing the range of values of a
   statistical variate into a number of classes where the magnitude of the
   range of each class is the same.  See also Class.

Excluded Zone - A zone displayed on the map and coloured with a special
   shade indicating that it has not been used for quantization or has been
   omitted from the area of interest.

File - A number of data items grouped together and considered as a unit for
   convenience of storage and retrieval by a computer.  Within OzGIS,
   such files are stored as distinct entities on disk.  Files are
   identified by media designation, name, and type.  The OzGIS user
   normally supplies only the file name, but the storage media may also be
   specified.  The file type is supplied by the system.  The same name may
   be used for files of different types, but within a particular type, no
   two files may have the same name.

Frequency - A statistical term referring to the number of members of a
   population falling into a specified class.  See also Class.

Geographic Data - Digitized map data which are referenced to a geographic
   (or spatial) coordinate system, usually a map projection.

Graphics - Data which can be displayed on the monitor in terms of lines
   points and text, as opposed to colouring and filling regions of the
   screen.  Used to refer to geographic and symbol data.

Histogram - A type of bar graph in which vertical rectangles are erected on
   the horizontal axis with the height of each bar representing the
   frequency, and the width representing the corresponding class interval,
   for each of the classes of a particular variate.  OzGIS can display
   such statistical information on the monitor.  See also Scatter Diagram,
   and Class.


Information - The subjective knowledge which may be associated with an
   objective set of data.  The ages and locations of children are data;
   the distribution of school age children is statistic;  where the schools
   should be built is information.  See also Data and Statistics.

Interval - The numerical distance between the upper and lower limits of a
   class.

Joystick - An electro-mechanical device which converts the positions of a
   small lever into electrical voltages.  The voltages are further
   converted into digital signals which are used by the PDP11 to
   position various cursor patterns on the monitor screen.  See also Box
   Cursor, and Crosshair Cursor.

Legend - A display on the monitor which indicates the correspondence
   between the statistical values and their associated colours or symbols
   as defined for a particular map.  The legend usually occupies
   approximately the rightmost one fifth of the viewing area of the monitor
   and has two general forms, single variate and bivariate.  One type of
   single variate legend consists of a column of coloured rectangles beside
   which are numbers indicating the corresponding class boundaries for

                                                                     197
   those colours.  The other is a rectangular column with colours gradually
   changing from top to bottom, and an upper and lower number indicating
   the range across which the "Continous Colour" varies.  The bivariate
   legend consists of a 45 degree parallelogram divided left to right and
   up and down into coloured smaller parallelograms.  A set of numbers
   along the left side indicates the class boundaries of the primary
   variate, while similar numbers across the upper side indicate the
   secondary variate class boundaries.

Line - This term has three special meanings within OzGIS in addition to
   its normal English usage.  (1) Any set of contiguous segments comprising
   the section of a zone boundary which has one zone on its right and a
   second zone on its left as part of a map.  (2) Any contiguous set of
   segments as part of a graphics display.  (3) A set of alpha-numeric
   characters meant to be displayed as one row on either the monitor or the
   terminal.

Location - The position of a datum point, or pixel, on the monitor screen.
   This is given by its x and y coordinates, with the origin in the lower
   left hand corner.  The range of values depends on the display system.

Lookup Table (LUT) - A table in the display system which can modify the
   value in memory for display purposes.

Map - Geographic data which can be displayed on the monitor by colouring
   and filling regions of the screen or as lines or symbols.

Map Projection - Refers to the coordinate system used for processing the
   display of a map.


Markers - Special characters or symbols which may be displayed on the
   monitor to identify locations of points.  For example, aircraft
   symbols to indicate the location of airports.  Different sized markers
   are used to show the classification of site attribute data.

Mean - The arithmetic average of a set of data values.

Memory - A portion of the OzGIS hardware used for the storage of data
   by the altering of the electrical state of the appropriate circuitry.

Menu - An itemized list of alternative actions which might be selected
   within OzGIS.  Menus are displayed on the terminal.  The terminal
   keyboard is used to enter selections from the options listed on the
   menu.  The sequence of menu items which is selected controls the "flow"
   of the OzGIS program through its various tasks.

Monitor - The electronic equipment, resembling a colour television
   receiver, on which maps and graphics are displayed.

Nested Means - A quantization method in which classes are generated by
   dividing each variate range into two classes about the mean for that
   range.  For example, the central class limit is set at the overall mean,
   then the upper and lower classes are each divided at the means of the
   two parts, giving four classes.  This process may be repeated, giving
   eight classes.

Operating System - Computer software provided to facilitate usage of the

                                                                     198
   various computer resources available within the OzGIS system.

Overlay - As a noun, overlay refers to graphic data written on top of the
   existing display.  This is displayed on the monitor as though placed
   between the previous display and the viewer.  Overlays generally are
   entered in the refresh memory in single bit planes.
   As a verb, overlay refers to the act of adding graphics data to a
   display by putting it "on top of" the previous display.

Palette - An array of coloured rectangles which is displayed on the monitor
   at certain stages of OzGIS.  The palette shows a range of colours
   which are available for selection by the user.  Palettes are held as
   files within OzGIS.  Several palette files are provided as part of
   the software package.

Parameter - A general term referring to a physical characteristic which may
   be measured or quantified in some way, even though the precise value of
   that measurement may be unknown in specific instances.  For example, age
   is a parameter of human beings.

Percentile - One of the set of 99 values which divide the range of a
   statistic into 100 equal sized classes.

Peripherals - Items of auxillary equipment added to a computer to enhance
   its performance.  These include such items as disc drives, tape drives,
   and printers.


Pixel - The smallest, individually controllable, element (or cell)
   displayed as dots of colour on the monitor's screen.  The monitor area
   is made up of lines of pixels.  For each pixel, there is a corresponding
   location in the refresh memory for storing the data value associated
   with that pixel.  This location is the smallest datum area which can be
   individually controlled by the software.  See also Image and Location.

Point - A geographic feature which, for display purposes, may be described
   by only indicating its location as an x and y coordinate.

Polygon - A geographic area described by the line segments forming its
   boundary and the zone name which forms its surface.  One or more
   polygons may be combined to form a zone.

Presentation Maps - A set of maps prepared for rapid display on the
   monitor.

Primary Variate - The set of statistical values characterized by a common
   name which is displayed on any given single variate map.  Two such sets
   of values are displayed on a bivariate map.  The primary variate is
   named at the top of the title, and its colour values are indicated in
   the rows of the legend.  See also Variate.

Processor - The hardware which executes the procedural and computational
   tasks specified by OzGIS.  The standard OzGIS processor is a
   Digital Equipment Corporation minicomputer, the VAX.

 Projection - The representation of a physical shape on the screen of the
   monitor according to a fixed mathematical coordinate system.  Normally,
   a projection in OzGIS terms will refer to a method for presenting

                                                                     199
   maps of geographic areas.  See also Map Projection.

Quantile - Any of the specific values which divide the range of a statistic
   into equal sized classes.  Some values have other special terms, i.e.,
   if the range is divided into four classes, the boundary values are
   called quartiles.  See also Percentile.

Quantify - To assign a number or quantity to an otherwise unnumbered
   entity.  In particular, to assign a class number to a statistical value
   or zone name.

Quantization - The process of assigning class numbers to zones according to
   the value of the statistic for that zone.  Viewed the other way,
   quantization is the process of putting zones into classes.

Quartile - One of the three data values which divide the range of a variate
   into four equal sized classes.  See also Quantile and Percentile.

Raster - a term applied to image data.  In particular data handled on a
   line basis.


Refresh Memory - The portion of the hardware (within the display
   controller) which holds the digital data necessary to continuously
   regenerate the colour monitor display.  The cathode ray tube (CRT) of
   the monitor produces its display by electrically stimulating various
   phosphorus based compounds deposited on its face.  The colours thus
   produced fade rapidly with time and must be continually "refreshed".
   The data necessary to perform this refresh correctly is stored in the
   refresh memory.

Region - A designated portion of a map displayed on the monitor.  A region
   consists of one or more zones or parts of zones defined in some way
   (e.g. a circular region centered at a point on the map).  The concept of
   a region is important when the displayed map consists of several
   geographic areas.  In this context, a region consists of a window
   (geographic area) and its displayed viewport on the screen (screen
   area).  See also Area.

Save - To store on disc (or magnetic tape) all the pertinent data regarding
   a map displayed on the monitor.  The maps which are "saved" can later be
   fully regenerated with all details preserved.

Scatter Diagram - A two dimensional plot of points whose x and y
   coordinates are the values of the individual variates associated with
   those points.  Scatter diagrams are displayed on the monitor in
   conjunction with bivariate maps.  In this instance, each map zone is
   assigned a point on the diagram.  The y-coordinate of the point
   corresponds to the value of the primary variate for that zone as
   displayed on the map.  The x-coordinate of the point has a similar
   relationship to the secondary variate.  In addition, the point will be
   coloured the same as its associated map zone.  Scatter diagrams provide
   a visual method of assessing the correlation between the two variates
   displayed on the map.

Secondary Variate - The second set of statistical values which are
   displayed (along with a primary variate) on the map.  The
   secondary variate is named at the bottom of the title.  See also Primary

                                                                     200
   Variate.

Segment - A set of connected straight lines defined to OzGIS by
   specifying the coordinates of their starting, intermediate, and end
   points, along with the names of the two zones on either side of the
   lines.  Consequently, segments must represent a portion, or all, of the
   boundary between two zones.  See also Line and Boundary.

Site - A geographic location that has associated attribute data.  A site is
   defined by a name and fixed location e.g. a site could be a city or a
   retail store.

Standard Deviation - A statistical measure of the dispersion amongst a set
   of measured values.  The standard deviation is mathematically equivalent
   to the positive square root of the variance of the sample on which the
   statistic is based.


Statistics - A general term referring to:  1) The branch of mathematics
   involved with performing certain analytical calculations regarding
   various relationships among sets of numerical data, and 2) The numerical
   results of such calculations.  The height of an individual is data;  the
   average height of a group is a statistic.

Status - The present condition of the software and hardware system,
   especially as to its progress toward the completion of the tasks at
   hand.  The status messages are displayed as a response to
   typing interpretation of various abbreviated messages displayed on the
   terminal.  The status messages are displayed as a response to typing an
   "S" command.

Terminal - An item of hardware comprising a keyboard for entering commands
   to the processor, and some means for the processor to return
   alpha-numeric messages to the user.  The standard OzGIS terminal is
   the Digital Equipment Corporation VT100.  This contains the necessary
   keyboard, and a cathode ray tube for displaying processor generated
   messages.  Some OzGIS installations may also have a printer terminal
   for providing a permanent copy of the messages on paper.

Territory - a zone which has been formed by amalgamating bas zones e.g. sales
   territories formed from postcodes.

Text - Combinations of characters which may be specified by typing at the
   terminal.  Lines of text may be displayed on either the terminal or the
   monitor in various fonts.  See also Character, and Line.

Time Lapse Maps - A formatted set of maps concerning a geographic area and
   certain statistics associated with it as they have been collected over
   time.  Time lapse files are used to display the time related changes in
   the statistical data by rapid and periodic changes in map colours
   corresponding to the statistics.  For example, variations in population
   density, as recorded by the 1971, 1976, and 1981 census data, could be
   shown by changing the colours of the displayed map at one second
   intervals corresponding to the 3 sets of data.

User - The person who is interactively controlling the OzGIS system at
   the terminal.


                                                                     201
Value - The number associated with a particular statistical item, as
   opposed to the colour associated with that item.  For example, the zone
   might be coloured red to indicate four to ten beer drinkers per pub in
   that zone.  The actual value of the statistic might be 9.4 beer drinkers
   per pub.

Variate - A measurable quantity which may take on any of the values within
   a given range, and which has associated with it a specified probability
   function describing the manner in which the permissible values are
   likely to occur.  See also Bivariate, Primary Variate, and Secondary
   Variate.

Viewport - The rectangular area of the colour monitor face selected for
   displaying a specified item.

Window - The rectangular portion of a geographic map which is selected for
   display on the colour monitor.


Zone - A geographic area which is to be considered as a spatial unit.  A
   zone is defined in terms of one or more polygons which form it.
   Statistically, a zone is defined in terms of a single value for each
   variate in question.  This relationship of one variate value per defined
   geographic zone allows zones to be completely and uniformly coloured in
   a map display.  See also Polygon and Variate.

Zone Name - An alphanumeric designation attached to the various
   computerized data associated with a zone.  The zone name facilitates for
   the processor the task of relating various data items to the proper
   zones.

                                                                     202
                     E. SYSTEM LIMITS
                       =============

The OzGIS system has a standard set of limits to various maximum counts. These
correspond to array sizes.


The standard limits are:-

     WINDOWS

    30000  max no displayed zones+sites+lines
    30000  max no values in attribute file (zones,sites,lines)
    100    max no map regions
    100    max no quantised zone geog files
    100    max no quantised site geog files
    100    max no quantised line geog files
    100    max no line overlays
    100    max no polygon underlays
    100    max no marker overlays
    100    max no name overlays
    100    max no text strings displayed
    500    max no polygons in a zone
    5000   max no segments in a polygon
    100    max no segments in a line
    5000   max no vertices in a segment
    20000  max no points in a fast display polygon
    1000   max no zones per item in a combine file
    256    max length of display system LUT (number colours)
    50000  max no vertices in foreign segments data file
    30000  max no zones that can be built from line segments
    10000  max no vertices in object for spatial operations
     5000  max no items in a text attribute file
    15000  max no zones in a catchment
           max no points in a catchment polygon
           max no contours in a site catchment
   120000  max no sitesXpoints for location allocation

                                                                     203
                     F. TROUBLE-SHOOTING
                       ================

Startup problems are usually caused by not defining the WINDOWS group items
properly. You cannot simply execute the WOZGIS.EXE file directly from the file
manager as the directory has to be defined.

"Not Enough Memory" problems are usually just that. You need 4 Meg of RAM, and
if you have network software etc loaded you may not have enough space. Note
that the system will not run on a 286. A swap file may enable the software to
run.

The development machine has 4Meg of RAM and runs WINDOWS 3.1 with a default
installation. The DOS "MEM" command gives:

    655360 bytes total conventional memory
    655360 bytes available to MS-DOS
    545328 largest executable program size

   1048576 bytes total EMS memory
   1048576 bytes free EMS memory

   3407872 bytes total contiguous extended memory
         0 bytes available contiguous extended memory
   1048576 bytes available XMS memory
           MS-DOS resident in High Memory Area

If no text appears on maps the fonts used are probably not installed. See the
installation chapter on \ozgis\ozgis.ini

There seems to be a bug in WINDOWS printing in that black backgrounds are
not properly filled- use a device file with a white background e.g. *WINSV

There is a serious incompatibility (bug) in that dialog boxes are not
automatically cleared under Windows 3.11 We do not know how to get around this
without a full rewrite and massive loss of speed (as the map would have to
be continually redrawn). We are waiting for WINDOWS 95.

IO errors can be caused initially by lack of disk space. Some processing
uses a lot of disk space as scratch files.
If you have trouble with menus reload the \ozgis\ozgis.men file. This file
defines all the menus and actions and is constantly rewritten. A hardware error
could corrupt the file.

Check the osgis.out file after problems to see if there are any error messages.
Also look in windows.out

The system generates scratch files with names ZZ... You have have to delete
them sometimes.
GIS data (digitised data) are often incorrect. This can cause problems with
polygon display e.g. if zone boundaries cross themselves, and during zone
building. Your data supplier probably wont be of much help. Try windowing into
the part of the map with problems to isolate it and use the debug option to
print values. You will have to patch the data files with a word processor.

Rebooting the system while the OzGIS programs are running can cause "loss" of
disk space. This can be recovered using CHKDSK.

                                                                     204
                     G. REFERENCES
                       ==========


O'CALLAGHAN, J.F., SIMONS, L. and PALMER, J.A.B. (1980).  A prototype
system for interactive colour mapping.  Proc. URPIS-8 (k. Davies (ed.)),
Surfers Paradise, pp. 9.1-9.5.

SIMONS, L., O'CALLAGHAN, J.F. and PAINE, T. (1982).  COLOURMAP - an
interactive colour mapping workstation.  Proc. DECUS (Digital Equipment
Computer Users Society), Melbourne, Vol. 10, pp.1501-1504.

O'CALLAGHAN J.F., and SIMONS, L.W.J. (1983) COLOURMAP: An Interactive
Colour Mapping System. Proc. First Australasian Conference on Computer
Graphics, Sydney.

O'CALLAGHAN J.F., and SIMONS, L.W.J. (1984).   Map Display Techniques for
Interactive Colour Mapping.

Henzell, O'Callaghan. A Sequential Line Simplification Algorithm based on
Equivalent Height. CSIRONET Technical Report, May 1980

Robertson, O'Callaghan. The Generation of Colour Sequences for Univariate and
Bivariate Mapping. IEEE Computer Graphics and Applications, February 1986.

Gerald Evenden. Cartographic Projection Procedures for the UNIX Environment - A
User's Manual. USGS open-file report 90-284.

TIGER/Line Census Files, 1990 Technical Documentation / prepared
by the Bureau of the Census. Washington:  The Bureau, 1991.

Atef A Elassal. General Cartographic Transformation Package (GCTP), Version ii
NOAA Technical Report NOS 124 CGS 9

J Sibert, 'Continuous-colour Choropleth Maps', Geo-Processing, (1980)
207-216.

'The Harvard Library of Computer Graphics Mapping Collection', Harvard
University.

E Giamottic and P Puliafits, 'An Interactive Spatial Information System: A
Tool for Regional Planning'; Proc IFIP 79.

J Dalton et al, 'Interactive Colour Map Displays of Domestic Information',
Proc SIGGRAPH 79, Computer Graphics, Vol 13 No 2 ACM/SiGGRAPH.

A Robinson et al, 'Elements of Cartography', Wiley 1978.


D Des Jardins, 'Multi-Level Statistical Maps in Graphic Communication',
Proc NCGA, Anaheim 1982.

"ACORD: AUTOMATIC COUNTOURING OF RAW DATA, Computers & Geosciences,
vol. 8, no. 1, p. 97-101, 1982", by D.F. Watson.

L Cooper, 'Location allocation problems', Operatons Research 11, p 331-343
1963.

                                                                     205

Goodchild and Massam, 'The transportation-location problem', Operations
Research 20, 1969.

Tornqvist et al, Multiple Location Analysis, 1971.

                    CONTENTS

  1. OzGIS INTRODUCTION                                              4
  1. 1 Programs                                                      4
  1. 2 Concepts                                                      4
  1. 3 Environment                                                   5
  2. INSTALLATION                                                    7
  2. 1 Installation                                                  7
  2. 2 Documentation                                                 7
  2. 3 Directories                                                   7
  2. 4 Environment                                                   8
  2. 5 Display Drivers                                               8
  2. 6 Installion in WINDOWS                                         8
  2. 7 OzGIS initialisation file                                     9
  2. 8 Demonstration                                                10
  2. 9 First Example Map                                            10
  2.10 Second Example Map                                           11
  2.11 Hardcopy configuration                                       11
  3. DATA ENTRY                                                     12
  3. 1 Introduction                                                 12
  3. 2 Example of data entry                                        13
  3. 3 Demonstration Files                                          15
  3. 4 Example geographic and attribute data                        15
  3. 5 Example device files                                         17
  3. 6 Marker data files                                            17
  3. 7 Colour names data (no longer used)                           17
  4. BASIC CHOROPLETH MAPPING EXAMPLE                               18
  4. 1 Simple Census-type Mapping                                   18
  4. 2 Example Choropleth Map                                       18
  4. 3 Summary                                                      20
  5. INTERACTIVE USER INTERFACE TO OzGIS                            22
  5. 1 OzGIS Menus                                                  22
  5. 2 Question Dialog Boxes                                        23
  5. 3 Command Dialog Boxes                                         23
  5. 4 Graphic interaction                                          24
  5. 5  Print file                                                  24
  6. OzGIS FILES                                                    25
  6. 1 File Origins                                                 25
  6. 2 File types                                                   26
  6. 3 File Names                                                   28
  6. 4 Directories                                                  29
  7. DEVICE FILES                                                   30
  8. OzGIS MAP TYPES                                                33
  8. 1 Map Types                                                    33
  8. 2 Attribute maps                                               33
  8. 2. 1 Bivariate zones map Example                               34
  8. 2. 2 Zones & sites Example                                     34
  8. 2. 3 Geographic (GIS) maps Example                             35
  8. 2. 4 Diagrams Example                                          37
  8. 3 Presentations                                                38
  8. 4 Saved-display files                                          38
  8. 5 Time Lapse Display (not available)                           38
  9. ATTRIBUTE SELECTION                                            39
  9. 1 Introduction                                                 39
  9. 2 From a list                                                  39
  9. 3 Sequentially                                                 39
  9. 4 By number (position in file)                                 39
  9. 5 By attribute description                                     39

  9. 6 By arithmetic operation                                      40
  9. 7 Zone/Site/Line names                                         40
 10. QUANTISATION                                                   41
 10. 1 Introduction                                                 41
 10. 2 Quantisation Methods                                         42
 10. 3 Quantisation Ranges                                          44
 10. 4 Quantisation Lists                                           44
 11. GEOGRAPHIC OVERLAYS                                            46
 11. 1 Introduction                                                 46
 11. 2 USA Census / TIGER Overlays Example                          47
 12.  DISPLAY CONTROL & MAP DESIGN                                  49
 12. 1 Introduction                                                 49
 12. 2  Map Quantisation Legends                                    49
 12. 3 Overlays (GIS) legends                                       51
 12. 4 Other Legends                                                51
 12. 5 Text                                                         51
 12. 6 Attribute Diagrams                                           51
 12. 7 Displayed Colours (removed)                                  52
 13. MAP REGIONS                                                    54
 13. 1 Introduction                                                 54
 13. 2 Regions                                                      55
 13. 3 Map List                                                     56
 13. 4 Quantised Zones                                              56
 13. 5 Quantised lines                                              57
 13. 6 Quantised sites                                              57
 13. 7 Line Overlays                                                57
 13. 8 Polygon underlays                                            58
 13. 9 Marker Overlays                                              58
 13.10 Name Overlays                                                58
 13.11 Map Modification                                             58
 14.  MAP ANALYSIS                                                  59
 14. 1 Introduction                                                 59
 14. 2 Map Reports                                                  59
 14. 3 Attribute Data Statistics                                    59
 14. 4 Map Interrogation                                            60
 15. DATA PREPARATION                                               62
 15. 1 Introduction                                                 62
 15. 2 Attribute Files                                              62
 15. 3 Geographic Files                                             63
 15. 4  Names Files                                                 64
 15. 5  Output to Data Files                                        64
 15. 6 Palette Files (Removed from system)                          65
 15. 7 Colour Names Files  (Removed from system)                    65
 16. BUILDING ZONES FROM SEGMENTS                                   66
 16. 1 Use                                                          66
 16. 2 Faulty Digitised Data                                        67
 16. 3 Example                                                      67
 17. WK1 INTERFACE TO OTHER SOFTWARE                                69
 17. 1 Introduction                                                 69
 17. 2 Attribute data                                               69
 17. 3 Names Files (lists of names)                                 70
 17. 4 Points                                                       70
 17. 5 Territories and Catchments                                   70
 17. 6 Addresses                                                    70
 18. MAP PROJECTIONS                                                71
 18. 1 Introduction                                                 71
 18. 2 Precision                                                    71
 18. 3 Latitude / longitude                                         71

 18. 4 Projections                                                  72
 18. 5 Ellipsoids                                                   72
 18. 6 Use                                                          73
 18. 7 Example                                                      73
 19. HARDCOPY MAP PRODUCTION                                        74
 19. 1 Overview                                                     74
 19. 2 Procedure                                                    75
 19. 3 Photographs                                                  75
 19. 4 OzMap Device files                                           76
 19. 5 VECTOR Program                                               76
 19. 6 OzMap Example                                                80
 19. 7 Fitting Maps on the Page                                     80
 20. TERRITORY DEFINITION                                           83
 21. ADDRESS MATCHING / GEOCODING                                   85
 21. 1 Introduction                                                 85
 21. 2 Addresses                                                    85
 21. 3 Data entry                                                   86
 21. 4 Address Matching                                             86
 21. 5 Matching Addresses                                           87
 21. 6 Procedure                                                    87
 21. 7 Data                                                         88
 21. 8 Abbreviations parameter file                                 89
 21. 9 Handling Errors                                              89
 22. SPATIAL OPERATIONS                                             91
 22. 1 Operations                                                   91
 22. 2 Feature codes                                                92
 22. 3 Procedure                                                    92
 23. SITE LOCATION / ALLOCATION                                     94
 23. 1 Introduction                                                 94
 23. 2 Example                                                      94
 23. 3 Solutions                                                    95
 23. 4 Sites                                                        95
 23. 5 Geographic Data                                              95
 23. 6 Attribute data                                               96
 23. 7 Allocation                                                   96
 23. 8 Parameters                                                   96
 23. 9 Barriers and Freeways                                        97
 23.10 Outputs                                                      97
 24. SITE CATCHMENTS                                                98
 24. 1 Introduction                                                 98
 24. 2 First example                                               100
 24. 3 Data                                                        100
 24. 4 Example                                                     100
 24. 5 Geographic files                                            103
 24. 6 Catchment files                                             103
 24. 7 Catchment modification                                      104
 25. DIGITAL CHART OF THE WORLD                                    106
 25. 1 Introduction                                                106
 25. 2 Databases                                                   106
 25. 3 Files                                                       106
 25. 4 Utilities                                                   106
 25. 5 Coverage directories                                        107
 25. 6 Directory Contents                                          108
 25. 7 Example - World Countries                                   110
 25. 8 Tiles Example                                               112
 25. 9 Polygons                                                    116
 25.10 Summary                                                     116
 25.11 Other VPF data                                              117

  A. MAP DATA FORMATS                                              118
  A. 1 Introduction                                                118
  A. 2 OzGIS data Formats                                          118
  A. 3 Description of File Formats                                 119
  A. 4 Format of attribute files                                   120
  A. 4. 1 Preprocessing                                            120
  A. 4. 2 OzGIS Standard Format                                    120
  A. 4. 3 Sample attribute file DEMOATTR.DAT                       121
  A. 4. 4 Simple Attribute format (tabular database format)        121
  A. 4. 5 Sample simple attribute file DEMOSASA.DAT                121
  A. 4. 6 Spreadsheet WK1 format (Lotus, Excel etc)                122
  A. 4. 7 ATLAS Data files                                         123
  A. 4. 8 LAMM format                                              123
  A. 4. 9 Comma delimited format                                   124
  A. 4.10 Australian 1991 Census format                            125
  A. 4.11 Other attribute data formats                             125
  A. 5 Text Attribute files                                        126
  A. 6 Standard OzGIS formats for geographic files                 127
  A. 6. 1 General Information                                      127
  A. 6. 2 Structure of data                                        127
  A. 6. 3 Internal Data                                            128
  A. 6. 4 Comment Record                                           128
  A. 6. 5 Map Partition                                            128
  A. 6. 6 Zones Partition                                          129
  A. 6. 7 Line Partition                                           129
  A. 6. 8 Polygons Partition                                       130
  A. 6. 9 Segments Partition                                       130
  A. 6.10 Points Partitions                                        132
  A. 6.11 Sample boundaries geographic file DEMOZSEG.DAT           132
  A. 6.12 Sample segments file with adddresses DEMOADDR.DAT        133
  A. 6.13 Sample lines geographic file DEMOLINES.DAT               135
  A. 6.14 Sample points geographic file DEMOPOINT.DAT              136
  A. 7 Format of polygon geographic files                          137
  A. 7. 1 Standard (not implemented)                               137
  A. 7. 2 SAS Format Zone Files                                    137
  A. 7. 3 Simple Format (old SAS) Zone Files                       138
  A. 7. 4 Sample simple zones data file DEMOSASG.DAT               139
  A. 8 GIS / common geographic file formats                        140
  A. 8. 1 DIME format                                              140
  A. 8. 2 DLG optional 3 format                                    140
  A. 8. 3 Gina format                                              142
  A. 8. 4 ANSII standard                                           144
  A. 8. 5 SIF format (not available)                               144
  A. 8. 6 DXF format                                               145
  A. 8. 7 Digital Chart of the World                               146
  A. 8. 8 IDRISI Vector Format                                     146
  A. 8. 9 ATLAS Export Format                                      147
  A. 8.10 MapInfo Data Interchange Format                          150
  A. 9 Format of names files                                       153
  A. 9. 1 Sample names file DEMOATTR.DAT                           153
  A.10 Format of colour names files (Removed from system)          153
  A.11 Format of combine files                                     154
  A.11. 1 Sample combine file DEMOCOMB.DAT                         154
  A.12 Format of presentation files                                154
  A.12. 1 Sample presentation file                                 155
  A.13 Format of marker files                                      155
  A.13. 1 Sample marker file SQUARE.DAT                            156
  A.14 Format of device files                                      156

  B. USA Census data                                               162
  B. 1 Overview                                                    162
  B. 2 Documentation                                               163
  B. 3 OzGIS Processing of TIGER data                              163
  B. 4 Processing STF1A data                                       164
  B. 5 The STF1A parameter file                                    165
  B. 6 Example                                                     166
  B. 7 OzGIS Census Zone Names                                     175
  B. 8 STF1A Census data                                           175
  B. 9 STF1A Geographic areas                                      175
  B. 9. 1 Blocks                                                   175
  B. 9. 2 Block Groups                                             176
  B. 9. 3 Census tract and block numbering area                    176
  B. 9. 4 Census Tract                                             177
  B. 9. 5 County                                                   177
  B. 9. 6 Hierarchical Presentation                                178
  B. 9. 7 Zip codes                                                178
  B.10 The STF1A file                                              179
  B.10. 1 File Segments                                            179
  B.10. 2 Field Names In Numeric Data Tables                       180
  B.11  TIGER US Census Digital Map Data                           180
  B.12  TIGER files                                                180
  B.13 TIGER Geographic Area Definitions                           182
  B.14 TIGER feature codes                                         184
  C. CONFIGURING OZGIS                                             190
  C. 1 Hardcopy configuration for  OzMap                           190
  C. 2 Plotter setup                                               191
  D. GLOSSARY OF TERMS                                             193
  E. SYSTEM LIMITS                                                 202
  F. TROUBLE-SHOOTING                                              203
  G. REFERENCES                                                    204