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OzGIS V8.8 (September 1992) Geismar Holdings Pty Ltd. QMDD Box 6108 Queanbeyan, Australia 2620. 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. This manual describes the IBM PC version. Some of the facilities that were available on the PDP11 and VAX systems have not yet been ported. 3 Geismar Holdings 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 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 system consists of several modules: OzEnter - for entry of data files into the system. OzData - preparation of data for mapping OzZone - formation of zones / polygons 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 OzProj - map projections Being tested are: OzSpat - spatial operations OzDigit - digitising WINDOWS3.1 version Start by using OzCensus; its a simpler version of OzGIS suitable for Census-type mapping. 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 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 5 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 interactive version, and the SCIPLOT package for hardcopy map production. 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. The WINDOWS version (under development) will enable extended memory to be used. A PC with at least 4Meg of RAM and a mouse will be required. The interface to the API is coded in 'C'. Generally the speed of the system is dependent on hardware: 6 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. SUMMARY ======= This chapter provides an overview of the facilities provided by the OzGIS suite of programs. OzGIS was designed to: . facilitate the interpretation of the spatial distributions of data . prepare maps to be output on printers and plotters . assist the analysis and modelling of spatial relationships in data The system can therefore be used to analyse socio-economic data produced by censuses and surveys and to support management decisions associated with for example Government planning, marketing, sales, site and personnel location, advertising and natural resources. Products: . Zone maps displaying polygons that are filled (with colours, patterns or hatching) to show the distribution of attribute data . Line maps displaying lines in different line patterns to show the attribute data distribution . Site maps displaying symbols at locations where the symbol sizes show the attribute data distribution . Bivariate maps showing filled zones for two attribute files . Zone and line maps showing lines overlayed on zones for two attribute files Zone and site maps showing site symbols overlayed on zones for two attribute files . Geographic maps displaying polygons, line segments, symbols or site names according to feature codes but without reference to attribute files . Histograms showing the number of items (zones, lines or sites) assigned to each class, or the number of items within value intervals (distribution) or the attribute values sorted in ascending order . Scatter diagram for two attributes . Map statistics . Map reports Files: . Data files are raw Ascii data files in a variety of external formats. Standard GIS formats and formats from Census Bureaus and Mapping Agencies are supported . Geographic files describe geographic data in terms of the graphic elements zones, polygons,line networks, line segments, and points . Attribute files contain the values of attributes (variates, statistics, variables) referenced to zones, line or site names. . Names files contain a list of zones, lines or sites that defines a region of interest . Combine files define new items in terms of zones for aggregation . Marker files define simple shapes as polygons for display as symbols 8 . Saved display files contain the information to regenerate a complete map . Device files define the graphics devices and their capabilities; colours, fonts, line types, hatching, markers etc . Parameter files contain special data for some processing. . Presentation files define a series of maps for demonstrations. User Interface: . Menu / windows interface . Help facility . Trace information . File interrogation, audits, deletion . Tutorials Data processing . Subsetting of geographic files . Line segment simplification . Joining short line segments for polygons . Amalgamation of geographic and attribute data . New attributes by arithmetic and logical expression . Building zones structure from line segments . Generation of names files . Generation of template attribute data files . Map projections . Address matching Quantisation . Classification methods: equal value, quantiles, specified intervals, specified number, refined, sequential colour, mean and standard deviations, nested means, natural breaks, percentiles, fixed . Quantisation over value ranges . Quantisation for lists of items . Independent quantisation for one or two files Map regions . Display of several geographic files at the same time, joined together or as multiple regions . Windowing and viewporting for layout . Coordinate grids . Overlays of line segments, polygons, names and symbols Attribute selection . Sequentially off attribute file . By position in file . By description Map enhancement . Specification of legend contents . Addition of text . Addition of histograms showing distributions, sorted values or quantisation results . Addition of scatter diagrams to bivariate maps . Overlay of mean and standard deviation, median and regression curves on 9 diagrams Hardcopy Map Production . HP compatible plotters . Many dot matrix printers . Postscript laser printers . HPGL, CGM and word processor files Applications . Territory assignment . Site catchments (not available yet) Environment . Requires minimum of IBM PC compatible with hard disk, 640K RAM and EGA. . Preferred hardware is AT compatible with 512K super VGA card giving 256 colours at at least 640 x 480 resolution. 1Mbyte boards with Trident or Tseng Labs 4000 chipsets are recommended. . MS DOS operating system Under Development . WINDOWS 3.1 version . Spatial operations (polygon overlay etc) . Digitising (being ported from Vax) 10 3. SYSTEM CONFIGURATION ==================== This chapter describes how to set up the OzGIS system and how to make the best use of your hardware. 3. 1 Introduction ------------ Various parameter files have to be set up correctly before the system can be used, as OzGIS supports a range of video boards. This should be quite straight forward for standard EGA and VGA boards, but as there are no standards for super VGA boards the procedure may get involved. The configuration is worth spending the time on as it is very important to display maps as fast as possible and to use the highest display resolution possible. If you plan to do a lot of mapping it is worth purchasing good hardware (its optional). Resolution is provided by using Super VGA boards. Speed is provided by: . Super VGA boards with 256 colours (512K or 1 Mbyte RAM on the board) . Using an extra 1MByte of RAM as a RAM disk. . Math coprocessor . fast processors (386 / 486) The other hardware worth having is a mouse. While the arrows on the keyboard can be used, they are slow. FOLLOW THE INSTRUCTIONS CAREFULLY! 3. 2 DOS system files ----------------- The start-up command file AUTOEXEC.BAT will have to be modified so the programs can be accessed by changing the path statement to reference /ozgis. e.g. PATH C:\DOS;C:\PROGS;C:\OZGIS The system file CONFIG.SYS has to have: FILES=20 BUFFERS=20 These changes to the DOS system files will not take effect until the system is 11 re-booted. 3. 3 Standard EGA and VGA boards ---------------------------- If you have a super VGA board SKIP this section. You need to be aware of the resolution of your video card. This is one of: 350 lines of 640 pixels for EGA 480 lines of 640 pixels for VGA Both boards have 16 colours. You now need to check two configuration files: All the following take place in the \ozgis directory. The file \OZGIS\OZGIS.INI is the initialisation file for the system. This file has to be modified using your word-processor. 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 be either: for the EGA board 640 Number of pixels across EGA screen 350 Number of lines on screen 16 Number of colours or for the VGA board 640 Number of pixels across VGA screen 480 Number of lines on screen 16 Number of colours The file \OZGIS\INTERACT.INI is the initialisation file for the interactor graphics package. This file has to be modified using your word-processor. The file should be well commented, and modifications should be fairly obvious. If a standard VGA card is being used, nothing may have to be changed. If an EGA card is being used the display type may have to be set via the DISPLAY= parameter (colours will be strange). 12 3. 4 Super VGA boards ----------------- The recommended display is a super VGA board with the ability to display 256 colours at a resolution of at least 640 X 480, as this enables maps of up to 240 zones to be manipulated rapidly by changing the colours via the colour look-up table. 16 colour displays require the map polygons to be redrawn every time the colours change (e.g. by displaying another attribute). Hence you should use the highest resolution available with your board and monitor that gives 256 colours. (this may not be true if you are mapping e.g. environmental data without attribute data or have maps of more than 240 zones when resolution may be more important). First determine the resolution and number of colours you want to use. This will depend on the amount of memory on your board and the chipset. If in doubt read your video board manual or ask your computer shoppe. In order of preference the resolutions are: Pixels Lines Colours 1024 768 256 (1MByte boards) 800 600 256 (512K boards) 640 480 256 (512K boards with standard monitor) 800 600 16 (256K board) If your board has only 256K of memory you should consider adding more memory, but in the meantime use the highest resolution possible for 16 colours The boards supported by the graphics package are: Chipset Chipset 640x350 640x400 640x480 800x600 1024x768 Number Tseng 3000 0 y y y Tseng 4000 1 y y y y y Paradise 2 y y Video 7 3 y y y Everex 4 y y y y ATI 5 y y y Trident 6 y y y y Chips & Tech 7 y y y Ahead B 8 y y y Oak 9 y y The precise combination of modes available on any given board varies according to the manufacturer and the amount of video RAM available. The 640x480 and 800x600 modes require 512k and the 1024x768 mode requires 1 megabyte. You now need to modify two configuration files in the \ozgis directory. The file \OZGIS\OZGIS.INI is the initialisation file for the system. This file has to be modified using your word-processor. 13 The file should be well commented, and modifications should be fairly obvious. The first three lines have to be the resolution and number of colours e.g. 800 Number of pixels across VGA screen (640 - 1024) 600 Number of lines on screen (350 - 768) 256 Number of colours (16 or 256) Ensure that you dont alter the columns used i.e. the file is not free format! The file \OZGIS\INTERACT.INI is the initialisation file for the interactor graphics package. This file has to be modified using your word-processor. The file should be well commented, and modifications should be fairly obvious. The display type may have to be set via the DISPLAY= parameter. Super VGA boards require registers to be initialised. Look through the list and find yours. If its not there you may have to use the system as a standard VGA as described in the previous section, but first look in your video board manual to see if there is information about the registers to be used to set modes. If there is you may be able to set up an appropriate mode command as described in the following paragraphs (try it to see if it works). All you have to do is to is enable a command that corresponds to your video card e.g. if you have a 1Meg TSENG Labs ET4000 card you will find the following entry: REM mode13 = 56 0 0 0 1 1024 768 (1024x768 256-colour graphics) C All you have to do is remove the "REM " from the front (dont forget the blank i.e. left align it). You would normally also remove the comment too, so you end up with: mode13 = 56 0 0 0 1 1024 768 C (the "C" on the end is require with a mouse to tell the system to generate a cursor as mouse drivers normally do not do that with super VGAs). Try and find the corresponding entry for your board. If you are still confused try reading the appendix. The OzGIS system is now configured for your super VGA board. 3. 5 Maths Coprocessor ----------------- If you have a maths coprocessor you can use a different version of the main OZGIS program. 14 You need to modify the batch files \ozgis\ozgis.bat and \ozgis\ozcensus.bat to use the program ozgisco instead of ozgisprg. 3. 6 Extra RAM --------- If you have more than 1 Mbyte of RAM you can speed up display of menus and other windows enormously by using a RAM disk. You put a command in your config.sys file like: DEVICE=C:\DOS\RAMDRIVE.SYS 1024 /E This then gives you a pseudo disk drive in RAM, so its very fast. The drive identifier is one more than you are using e.g. if you have one disk drive called C: then the RAM disk drive will be D: After you have put in the command, reboot you PC and type "DIR D:" to check that you got it right (see your DOS manual). Now modify the \ozgis\interact.ini file to define the two save files to be on the RAM drive. The entries should look something like: TEMPMENU = D:\menu.tmp TEMPWINDOW = D:\window.tmp 3. 7 Mouse ----- If you have a mouse it must be installed in the standard way. The driver must be call MOUSE.COM (for the system to detect it). Mouse drivers usually only work with standard VGA and EGA. If you are operating in super VGA modes you would have to set the mode command in \ozgis\interact.ini with a "C" on the END (as already described) for the cursor to appear. 3. 8 Hardcopy configuration ---------------------- Configuration for production of hard-copy maps via OzMap is described in the appendix. 3. 9 Digitiser --------- Configuration for digitising is described in the relevant chapter 15 4. OzEnter DATA ENTRY ================== Map data are imported as data files into the OzGIS system. This chapter shows how to use the OzEnter program. 4. 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. OzEnter supports data files in several formats. 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 files are entered into the system via the OzEnter program which checks the data and writes them to internal files. The main menu enables selection of the type of file: INPUT GEOGRAPHIC FILES INPUT ATTRIBUTE FILES INPUT A NAMES FILE INPUT A COMBINE FILE INPUT A DEVICE FILE INPUT A MARKER FILE Choosing a menu item may generate another menu e.g. for GEOGRAPHIC FILES INPUT A STANDARD FORMAT GEOGRAPHIC FILE INPUT NEW FORMAT SAS GEOGRAPHIC FILE INPUT OLD FORMAT SAS GEOGRAPHIC FILE INPUT A DLG-3 OPTIONAL FORMAT GEOGRAPHIC FILE INPUT A GINA FORMAT GEOGRAPHIC FILE INPUT A TIGER FORMAT GEOGRAPHIC FILE INPUT A DIME FORMAT GEOGRAPHIC FILE INPUT 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 16 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 by the OzData program 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. 4. 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 to run the OzEnter program type: cd \ozdemo ozenter A menu will appear like: 1 TUTORIALS & SYSTEM INFORMATION 2 INPUT GEOGRAPHIC FILES 3 INPUT ATTRIBUTE FILES 4 INPUT A NAMES FILE 5 INPUT A COMBINE FILE 6 INPUT A DEVICE FILE 7 INPUT 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: --------------------------------------- 17 Select the option to INPUT GEOGRAPHIC FILES The next menu appears: 1 INPUT A STANDARD FORMAT GEOGRAPHIC FILE 2 INPUT NEW FORMAT SAS GEOGRAPHIC FILE 3 INPUT OLD FORMAT SAS GEOGRAPHIC FILE 4 INPUT A DLG-3 OPTIONAL FORMAT GEOGRAPHIC FILE 5 INPUT A GINA FORMAT GEOGRAPHIC FILE 6 INPUT A TIGER FORMAT GEOGRAPHIC FILE 7 INPUT A DIME FORMAT GEOGRAPHIC FILE 8 INPUT A DXF FORMAT GEOGRAPHIC FILE 9 INPUT 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 INPUT 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 type Esc to go back to the first menu. Now enter the attribute data: ----------------------------- select the option to INPUT ATTRIBUTE FILES A new menu appears: 1 INPUT A STANDARD FORMAT ATTRIBUTE FILE 2 INPUT A LOTUS 1-2-3 FORMAT ATTRIBUTE FILE 3 INPUT A DATABASE (SIMPLE) FORMAT ATTRIBUTE FILE 4 INPUT A LAMM FORMAT ATTRIBUTE FILE 5 INPUT USA CENSUS STF 1A FILES FOR TRACT/BNA 6 INPUT USA CENSUS STF 1A FILES FOR BLOCK GROUPS 7 INPUT ATLAS DATA FILES The data are in standard form so: Select INPUT 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 - 18 type F10 to exit If you type DIR "OZ.*" you will find that there are two new files there: 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. 4. 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 4. 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. Other files may also be supplied: Washington DC Census Tract/BNA and TIGER lines Africa in Atlas format Hawaii in DLG-3 optional format 19 4. 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 have already been used. 4. 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). 4. 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. 20 5. BASIC CHOROPLETH MAPPING EXAMPLE ================================ This chapter gives an introduction to the map display programs. 5. 1 OzCensus -------- The main display and analysis program is OzGIS. A much simpler version of OzGIS is provided called OzCensus. This version is suitable for simple mapping of Census type data and is recommended for use while learning to use the system. OzCensus has two or three menus and about twenty menu options while the full OzGIS version has about fifty menus and a few hundred menu options. When you want to do more advanced mapping use OzGIS! 5. 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 with the OzEnter program has been given in the last chapter. Both the attribute file and geographic file are called OZ. Different types of files can have the same name. To start the Census mapping program type: 21 cd \ozdemo ozcensus The first menu appears: 1 TUTORIALS & SYSTEM INFORMATION 2 DISPLAY A NEW MAP choose the option to "DISPLAY A NEW MAP". give the attribute file name as OZ. When asked for the geographic file name input "L". A list of the available files will appear (type Enter or Esc to exit). Give the geographic file name as OZ. 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: 1 TUTORIALS & SYSTEM INFORMATION 2 DISPLAY A NEW MAP 3 ADD TEXT TO MAP 4 DISPLAY THE NEXT SEQUENTIAL ATTRIBUTE 5 SELECT AN ATTRIBUTE FOR DISPLAY BY NUMBER 6 CHANGE THE NUMBER OF CLASSES 7 CHANGE THE QUANTISATION METHOD 8 DISPLAY ATTRIBUTE STATISTICS 9 LIST ZONES SELECTED WITH BOX-CURSOR 0 SAVE DISPLAY FOR HARDCOPY MAP GENERATION WITH OzMap Now investigate some of the options: Choose the option to DISPLAY THE NEXT SEQUENTIAL ATTRIBUTE If you only have 16 colours the system does not display the map until you request regeneration. This enables several options to be changed before the slow polygon drawing takes place. If the map does not change type F3 to regenerate the map. Select the option to SELECT AN ATTRIBUTE FOR DISPLAY BY NUMBER. Type 0 to get a list. A list of the attribes available will appear in a window. Type Esc to return to the question. Type in a number to select an attribute. (type F3 to regenerate if necessary) Now investigate some of the function keys: 22 (You should print the file FNKEYS.DOC for a template.) Type F1 to get a help message. Esc is usually used to return. F2 hides the menu; type Esc to redisplay it. F3 regenerates the map when required F4 enables files to be audited and maintained. Type F4 and select the option to interrogate files. Select geographic files and use the file name OZ (the one displayed). Type Esc three times to return to main menu (Esc is used to return to the previous menu). F6 enables 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. F8 causes a jump back to the previous main menu. This enables skipping back several levels. You will find that at main menus this is the only way to exit. (Irrelevant with the tiny number of menus in OzCensus). F10 is used to exit from the program. Dont use it yet! Back at the main menu, select CHANGE THE NUMBER OF CLASSES. change the number of classes to 10. (type F3 to regenerate if necessary) 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. (Type F3 to display) 23 Type Esc to go back to the main menu. Choose the option to DISPLAY ATTRIBUTE STATISTICS. Basic statistics will be displayed in a window for the displayed map. Type return (or Esc) 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. Type F10 to exit. 5. 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. 2. you usually set up a directory on the same disk as \OZGIS and put the data files there. 3. You use the OzEnter program to input the files. 4. You use either OzCensus or OzGIS to display the data. But ......... this is very simple You may want to use OzData to do some data preparation before mapping. You may have geographic data as line segments and need to use OzZone to form the polygons. You may want to display other types of maps or diagrams with OzGIS. You may want to output prepared maps to a printer, plotter or file with OzMap. and so on. 24 6. 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. 6. 1 Menus ----- 6. 1. 1 Menu format ----------- 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] 1: [menu item 1] 2: [menu item 2] : : : n: [menu item n] Menu items are numbered sequentially from one. A selection is made by typing in the character next to the item. Alternatively the arrows can be used to move up or down and Enter typed to select. You will find that some programs (e.g. OzGIS) have 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 iten to appear that allows you to delete that item. The general approach is: if the current menu does not have the option you want type Esc to go back to the previous menu and so on. 6. 1. 2 Function keys ------------- User interaction is provided at every menu by typing function keys: (print out \ozgis\fnkeys.doc for a template) F1 presents "help" or informative messages about the menu items and describes the effect of selection of the items 25 F2 enables the menu to be removed so it does not obscure the display. Esc will display it again. F3 regenerates the map after parameters have changed. Enter must be typed to display the next menu. F4 permits interrogation and maintenance of OzGIS files. A menu is presented with the following options: - delete a file - interrogate the header of a file - generate a list of files. F6 permits the extent of user communication to be controlled. A menu with the following options is presented: - turn user assistance messages on/off - turn trace messages from tasks on/off - turn the bell to signal cursor operation on/off - turn on debug (useful for reporting errors) The default of the option for user assistance messages is "on" (i.e., that the messages are displayed). The default of the option for trace messages depends on the module. (it is useful for data entry and preparation) The debug option is for system testing, but may be useful to trace faulty data problems. Output goes to the print file OZGIS.OUT F8 exits from the current menu to the last major menu, which depends on the stage of processing. F10 quit the OzGIS session. Pressing the "Esc" key before entering any other character has one of two effects: - return to the previous menu or - repeat of the current menu ("F8" should be typed to return to the previous main menu) The option taken depends upon the stage of processing. 6. 1. 3 Stacking selections ------------------- Menus take quite a time to display as the underlying graphics has to be stored first. A series of selections can be made when the sequence of menu options is known, and the menus will not appear. 6. 2 Questions --------- Questions are asked by OzGIS when data are required for an operation. The user must supply the data by entering appropriate responses on the keyboard. 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 26 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 typing either "Y" (for "YES") or "N" (for "NO"). The following single character responses provide assistance when answering 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. 6. 3 Commands -------- 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: TYPE FILENAME (TEST): 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. 27 "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. 6. 4 Graphic interaction ------------------- Graphic interaction in OzGIS involves the use of the mouse and/or arrow keys to control the cursors on the monitor. Use the left mouse button or type Enter to select the position. 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 F6 option) There are two types of cursors: 1. a pointer to select a position of object 2. a box to select a region. The bottom left corner is selected and then the other. 6. 5 Pop-up ------ The menus and windows operate in "pop-up" mode. This requires that the screen under the menu etc has to be saved to file before the menu appears so it can be restored. This is slow. Display speed can be increased by specifying the save files to be on RAM disk (if you have extended memory) by modifying the file name in the \ozgis\interact.ini file. 6. 6 Print file ----------- Every program generates printout on a file OZGIS.OUT. This includes: Reports Error messages Debug output 28 7. 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. 7. 1 File Origins ------------ Data files usually come from Census bureaux, map data suppliers or your corporate database. The file types will become obvious with use of the system. 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. The following kinds of files must be entered into OzGIS with the OzEnter program: - marker files - device files - presentation files 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 (no longer available) 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 29 7. 2 File types ---------- 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. 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 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 30 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. There are two modes. The screen is usually saved so the map can be rapidly displayed, but this is not relevant for later regeneration on plotters etc. 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 other systems. 31 (n) 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. (not ported from the VAX) 7. 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 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 specifying input data files in OzEnter. Similarly, parameter files often come from other systems with naming conventions, so a full file name can be given. 7. 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 *C16SV3 is the same as giving it as \OZGIS\C16SV3 User files can be in any directory but it MUST BE ON THE SAME DISK AS \OZGIS !!! 32 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. 33 8. DEVICE FILES ============ This chapter describes device files. It is very important to use a correct file for the number of colours of your EGA/VGA video card. 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: . 16 or 256 colour sets . 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. *C16SV5 is a 16 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: First of all to run the OzGIS program type: cd \ozdemo ozgis 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 *C16SV1 Select the option to DISPLAY DEVICE CHARACTERISTICS 34 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, so if bivariate maps are to be produced different device files should be used. Next a 16 colour bivariate file ------------------------------- Now choose a bivariate device file *C16BV1 and display that. The bivariate sequence will show a progression of colour in each dimension. There is a set of files for 16 colour displays, *C16SV1 to *C16SV9 for single variate maps, and *C16BV1 to *C16BV3 for bivariate maps. Next 256 colour files (super VGA only) -------------------------------------- There is also a set of files *C256SV1 to *C256SV9 and *C256BV1 to *C256BV3 for 256 colour boards. If you have a suitable board display one of these. The colour sequence will now be the complete 121 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 (*C16sv? or *C256SV?) and decide on one that you will use as the default device file. When you have decided on the default file type F10 to 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 ---------------- 35 The colour sequences are designed to provide a colour progression that can help interpret the pregression in values in the attribute data. 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. 36 9. OzGIS MAP TYPES =============== This chapter introduces the various types of maps and diagrams that can be displayed by the OzGIS program. 9. 1 Map Types --------- Several types of maps and diagrams can be displayed with OzGIS. When you start the OzGIS 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 9. 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 - 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. 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. 37 9. 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). Remember that you may have to type F3 to display the map. 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: CHANGE ATTRIBUTES DEFINE QUANTISATION CHANGE DISPLAY FEATURES DEFINE GEOGRAPHIC OVERLAYS DEFINE MAP REGIONS ANALYSE MAP DATA SAVE DISPLAY FEATURES These are the major groups of options and will be descibed in later chapters. Type F8 to return to the top menu. 9. 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. Use the LOWE1 and LOWE2 attribute files again, and the LOWE zones geographic file. Give the sites geographic file as LOWE-S1. This displayes a file with polygons coloured for one attribute and symbols sized for the other. Now we can add more sites. Choose DEFINE MAP REGIONS from the map menu, which shows a menu: CHANGE THE DISPLAYED ITEMS IN THE MAP CHANGE MAP REGION WINDOW (GEOGRAPHIC AREA) 38 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). Type F3 to regenerate the map. You will have a coloured zones map with different sized symbols according to the attribute values and different symbols for the two files. Use F8 (twice) to return to the top menu. 9. 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 OzZone. 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 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. Type F3 to regenerate if necessary. The main menu now appears for this type of map: 39 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. If necessary, type F3 to regenerate the map. 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 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). Type F8 to return to the top level geographic map menu and then F8 again. Be aware that you can type several menu selections without waiting for the menus to appear. 40 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. 9. 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 (and type F3 to show the results). 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 that seems to offer what you want. 41 9. 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. 9. 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. 9. 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. tribute values. 42 10. 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. 10. 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: DISPLAY THE NEXT SEQUENTIAL ATTRIBUTE SELECT AN ATTRIBUTE FOR DISPLAY BY NUMBER SELECT AN ATTRIBUTE FOR DISPLAY BY DESCRIPTION 10. 2 Sequentially ------------ This option will simply select the next attribute off the file. As usual F3 may have to be used to display the map. 10. 3 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. 10. 4 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. 10. 5 By arithmetic operation ----------------------- This option is not available now due to the limited PC memory. See the data preparation option in the OzData program. 43 10. 6 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. 44 11. 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. 11. 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. 45 11. 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 46 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 47 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. 11. 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. 11. 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). 48 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. 49 12. GEOGRAPHIC OVERLAYS =================== This chapter describes how geographic data such as roads and town locations can be overlayed on top of displayed maps. 12. 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 OzZone also contain approximate centroids of zones with labels being the zone names. 50 12. 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 OzEnter program, thinning with the OzData program, and finally building the zones with OzZone. WASHRAIL is a lines file of railroads created by extracting for feature codes 200 to 252 in OzEnter. WASHROAD is a lines file of all roads created by extracting for feature codes 100 to 148 in OzEnter. 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 OzZone 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 the zone names. You could of course use any file with differnt locations and 51 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. Finally hit F3 to regenerate the map in the default order. 52 13. 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. 13. 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: 13. 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 53 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 54 - 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. 13. 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. 13. 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 13. 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. 13. 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 55 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. 13. 7 Displayed Colours (removed) --------------------------- Options to change colours are no longer available in the DOS version. 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). (b) by a blue, green and red (B,G,R) triple. Values for each of the 56 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. 57 14. MAP REGIONS =========== This chapter describes the options that enable the geographic layout of a map to be defined. 14. 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 DEFINE 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. 58 14. 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 59 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 F3 must be typed to completely regenerate the map display. 14. 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. The DOS version of OzGIS can display up to 500 items. When the number of display items (plus standard features) is less than the length of the hardware LUT (number of simultaneous colours) the system can display the results of quantising zone attribute data extremely rapidly by changing the colours. When the number of items is too large the system has to revert to displaying each zone by polygon fill. 60 14. 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. 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. 14. 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). 14. 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). 61 14. 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. 14. 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. 14. 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. 14.10 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. 14.11 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. 62 15. MAP ANALYSIS ============= This chapter describes how you can find out more about the attribute data displayed on a map. 15. 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 15. 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 15. 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). 63 15. 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 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 the window. Sites (and zone centroids) are selected by points that lie inside the window. 64 16. OzData DATA PREPARATION ======================= This chapter describes options to prepare data for display and analysis. 16. 1 Introduction ------------ The raw data are input to the system using the OzEnter program. 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 OzData program. The main menu is of the form: PROCESS ATTRIBUTE FILES PROCESS GEOGRAPHIC FILES PROCESS NAMES FILES OUTPUT EXTERNAL DATA FILES 16. 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 A common application is preprocessing Census data before display to form 65 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. 16. 3 Geographic Files ---------------- The menu is of the following form: SUBSET FOR ZONES LIST SUBSET FOR LINES LIST 66 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. 16. 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. 16. 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 OUTPUT NAMES DATA FILE 67 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 with OzEnter as a database format attribute file. 16. 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. 16. 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. 68 17. OzZone BUILDING ZONES FROM SEGMENTS =================================== Geographic data, such as Census boundaries, are often supplied as lines which have to be connected to form polygons. This chapter describes the OzZone program which carries out this zone building process and outlines common preprocessing of this type of data. 17. 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 OzZone program 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. The OzZone program has been implemented as a separate program to provide maximum capacity on the PC. 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. 17. 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. 69 OzData 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 OzEnter to form an attribute file. Displaying both files with OzCensus will allow the file to be checked. 17. 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: Run OzEnter, select INPUT GEOGRAPHIC FILES and then INPUT 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: Start OzData, 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 use OzZone to build the polygons structure from the lines. The menu is: BUILD ZONES FROM LINE SEGMENTS INTO NEW GEOGRAPHIC FILE BUILD ZONES 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. Finally use OzGIS to display the result (using attribute file LOWE1 and geographic file TEMP3). 70 18. MAP PROJECTIONS =============== This chapter describes the options in the OzProj program for converting geographic files between coordinate systems. 18. 1 Introduction ------------ OzProj is a program that 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). OzProj is based on public domain software from USGS. 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: 71 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 72 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 OzEnter program. 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 used OzEnter to input 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 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. 73 19. OzMap 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. Often maps will be previewed on the screen and then output to a plotter, printer or file. 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 avector 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. 74 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. You use the F3 key to display the map on the current device. Initially this is the screen, but you can use CHANGE DISPLAY DEVICE to send it e.g. to a printer. 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 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. 75 The options DISPLAY DEVICE CHARACTERISTICS and CHANGE DEVICE FILE can be used to investigate the various device files. 19. 4 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 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 76 =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) 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 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 77 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. 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 78 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 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. 5 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 79 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. Type F3 to display the map on the screen. Now select CHANGE DISPLAY DEVICE choose the printer metafile via PRINTER METAFILE (for VECTOR program) Type F3 to output the map to the file; give the file name e.g. phred. Type F10 to exit OzMap. 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. 6 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 have at least a .25 inch left margin and a .5 inch bottom margin reserved. The HP 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 80 ------------------------------------------------------------------- | 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 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 81 20. OzTerr TERRITORY DEFINITION =========================== This chapter describes the OzTerr program which 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. The initial menu is: 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 full menu now appears: TUTORIALS & SYSTEM INFORMATION START NEW SET OF TERRITORIES INTERACTIVELY#4001 START NEW SET OF TERRITORIES FROM COMBINE FILE#4002 DISPLAY TERRITORY NAMES DEFINE NEW TERRITORY DELETE A TERRITORY 82 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 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 You have to type F3 whenever you want to see the quantisation applied to the map. 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 typing F3 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 in OzData to amalgamate the base zones and related attributes to get a geographic and attribute file for mapping by using the option OUTPUT TERRITORIES AS COMBINE FILE. 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. 83 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 84 given. 21. 3 Data entry ---------- Lines data can be entered with the OzEnter program. 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 OzData program 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. 85 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 OzData program. When the OzData program is executed the main menu is: 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 86 DESPERATION MATCHING FOR SITES MAPPING 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) 10 digits street number (optional) 30 bytes street name 10 digits postal (zip) code For example, the demonstration file DEMOMTCH.DAT looks like: EXAMPLE ADDRESSES FOR MATCHING - DEMOMTCH.DAT ADDRESS001 1 GReat north road 2600 87 666 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 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 ADDRESS019 40 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 88 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". 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 89 22. OzSpat SPATIAL OPERATIONS (being tested) ======================================== This chapter describes the OzSpatial program that enables 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. 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 forest trees feature codes 77 to 88 90 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 using OzEnter 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 zones will have been formed from line segments by using the OzZone program. The results of the polygon processing is a file of line segments that can be built into polygons with the OzZone program. 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 OzSpat program is executed the 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 UNION OF POLYGONS WITH SIMPLE POLYGONS FOR FEATURE CODES 91 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 OzZone program. 92 23. OzDigit DIGITISING (being ported from VAX) ========================================== This chapter desribes the OzDigit program for digitising paper maps to obtain data for input into the OzGIS system. DRAFT DOCUMENTATION 23. 1 Introduction ------------ Digitising is a tedious, soul-destrying job. If you can, obtain your data from commercial or other sources. If you cant, try and get someone else to do it for you (but not someone you love!) If all else fails, this program will allow you to produce accurately digitised and topologically correct geographic data files. One IMPORTANT point: It is easy to rapidly digitise a map, but it can take a long time to fix any digitising errors such as digitising a line twice. Hence...... Digitise in a logical, precise way. Do a small amount at a time, process the data to check it, and then do some more. In particular, the first time you try digitising, draw yourself a trivial map on a piece of paper and digitise that to work out the procedure. 23. 2 Configuration ------------- Summagraphics compatible digitisers are supported. These plug directly into a port in the PC and work by generating Ascii messages to the PC that look like keyboard input. Configuration involves editing a line in the \ozgis\ozgis.ini file to specify the port that is being used. 23. 3 Files ----- You specify three files to the OzDigit program: . The menu file describes the menu being used and where it is located on the board. . The digitiser file contains all the current digitised data (see below) 93 . An output data files is generated that is in standard geographic file format and is read into the system with OzEnter. The digitiser file actually contains the names of several other files, which you dont usually worry about, but some of which can be modified directly once you understand how the digitising process works. These other files all have the same name as the digitiser file. but with different extensions. for example: PHRED.DIG the digitiser file PHRED.CPS the control point file PHRED.FIT the parameters for the transformation PHRED.DGV the digitised data file PHRED.ZON the zone/poly names and feature codes file PHRED.LIN the line segment names and feature codes file PHRED.PNT the point names and feature codes file 23. 4 Preparation for Digitising -------------------------- First of all make sure that the paper map to be digitised is in good condition. If necessary iron it to make it flat and tape any rips. Fix the map to the digitiser board with tape. Remember that the very edge of the board may not be "active", so put it away from the edge. If the map is too big it can be moved later to do the rest of the digitising i.e. you can digitise it in pieces. The map should be close to horizontal on the board. 23. 5 Setting up the Menu ------------------- You control much of the digitising process from a paper menu that you stick on the digitiser board. If you have a big board you may find that you leave the menu stuck in the same place all the time. However, you may find that you often need to stick the menu on a corner of the map you are digitising, and may have to move it to digitise what is underneath. You can have different sizes and shapes of menus to allow for fitting it on the board according to the shape of the map being digitised. You start by drawing yourself a menu on some paper. The menu has 17 entries: the digits 0 to 9 "POLY" for zone / polygon internal points "PNT" for intersection points (or points or nodes) "LINE" for line segments "DELP" for delete point "DELS" for delete line segment "END" end-of-job, end of number 94 You draw the menus on rectangular pieces of paper on a grid: e.g. you may set up a menu of 3 columns and 6 rows as follows: ---------------------- | | | | | 0 | | END | | | | | ---------------------- | | | | | 1 | 2 | 3 | | | | | ---------------------- | | | | | 4 | 5 | 6 | | | | | ---------------------- | | | | | 7 | 8 | 9 | | | | | ---------------------- | | | | | ZONE | PNT | LINE | | | | | ---------------------- | | | | | DELP | DELS | | | | | | ---------------------- The menu boxes should all be the same size. If you are doing a lot of digitising you will probably draw up several menus such as a vertical 1 column, 17 rows menu, a horizontal 1 row 17 columns menu and perhaps both 3X6 and 6X3 rectangular menus or a 5x4 menu. Before you start digitising you have to stick the menu on the board, select the DEFINE DIGITISING MENU option from the main OzDigit menu, and digitise the four corners of the menu so the program knows where you have put it. You also have to give the number of rows and columns in the menu. Finally you give symbol that goes into each each menu location where row 1 is the top, and column 1 is the left. The symbols are those above, with blank being a menu location that is not used. The menu definition is written on a file and remains current until changed. You can move the menu on the board during the digitising process, but you then have to redefine the corners. So you usually dont move it if you can help it - ever! You use the menu by digitising a point within the square of the item you want to select. Numbers, which are identifiers, are selected by digitising the digits followed by EOJ. 95 23. 6 Control points -------------- When you digitise a point the OzDigit program reads it in digitiser board coordinates. These are usually in a range like 0 to 10,000 The program has to be able to convert these coordinates to the map coordinates such as latitude/longitude or UTM. This is done by digitising "control points". These are several points on the map at known map coordinates that are digitised at the start of data capture. The program knows both the board and map coordinates of each of the points, so can generate a function to transform any digitised point to map coordinates. First of all you select some suitable points on the map where you know the actual map coordinates - usually on the map grid. You should use at least four points near the corners of the part of the map being digitised and preferably at least one near the centre of the map too. You usually mark the points on the map with a coloured pen so you can remember which ones you used, and number them 1,2,3... Next select DEFINE CONTROL POINTS from the menu and define the points in turn giving an identifying number and the point in map coordinates (remember that for latitude longitude the X value is the longitude). The coordinates are given as decimals, and appropriate signs should be used e.g. latitude is negative below the equator like -35.0. The results are stored on a control points file and you can read in an existing file and overwrite the values in it. The digitising software does not use map projections. You can use the OzProj program for that purpose. Finally you have to digitise the points. You define the numbers by selecting from the menu digits followed by EOJ for the control point identifier, and then digitise the actual point. The first time you will have to digitise all the points, but after that only any that you might have changed. The program generates the transformation equation table -> map coordinates and prints out a goodness-of-fit. You can accept that or can modify the control point definitions. 23. 7 Digitising the Map ------------------ The OzDigit program is designed for digitising maps and producing data in a correct topological structure of zone-polygon-line where boundary lines occur once only (usually) and are shared between the adjacent polygons. This requires careful, logical digitising. 96 These types of maps are for choropleth mapping e.g. Census maps. However, the system can also be used to produce a subset such as just points, lines or simple polygons for production of map overlays (e.g. town locations, roads) or environmental applications e.g. vegetation type polygons where the polygons may not be adjacent. You start the digitising process by selecting DIGITISE NEW MAP DATA. The procedure for digitising Census type maps is: First of all digitise "nodes" which are the intersection points of all the boundary lines. Every node has a number (identifier) which can be generated sequentially by the system, but it is recommended that you assign your own numbers. You should prepare the map before digitising by writing the numbers against every place lines join/cross (some people use coloured stickers). Alternatively label each point as you digitise it. Ensure that you mark the points so you dont digitise them twice or miss any. Next you digitise the boundary lines. All lines start and end on a node. While digitising you can keep going along the map lines, but everytime you pass through a node you have to be sure that you digitise the node point so the program can connect to it. You usually find that you have missed labelling a few nodes. Lines also have numeric identifiers. As before they can be automatically assigned but it is recommended that you choose a range of numbers that is different to those used for the points and label the map either before you start or as you go. Ensure that you mark lines in some way as you go so you dont digitise lines twice and you dont miss any. If you have a large map you should digitise complete polygons in a small part of the map, ensure it is correct, and then do a bit more, until finished. Next you have to digitise internal points in each of the polygons that make up the zones. Once again you should label these points carefully, using a different range of numbers. In all cases you start digitising a map object by choosing the type from the digitiser menu i.e. ZONE, INT or LINE, and then the identifying number from the digits on the digitiser menu. You then start digitising the map data. You can digitise a sequence of objects without returning to the menu, in which case the identifying number is incremented for each object. The PC display will show the data as it is digitised. When EOJ is selected you are presented with several options for displaying and modifying the data. While you are digitising, the transformation is used to convert the locations to map coordinates. The digitised data is usually saved at the end of digitising and can be read back in next time. 97 If you are digitising data for overlays you may take a more casual approach as you are not concerned that lines can be joined into polygons. You may then digitise and allow nodes to be automatically generated. Polygons are then likely to be generated as closed lines, with the same node at each end. 23. 8 Examining digitised data ------------------------ You can choose the option EXAMINE DIGITISED DATA to plot points, lines or zones for ranges of identifying numbers. 23. 9 Giving Names and Feature codes ------------------------------ Zones (polygons), lines and points are identified by numbers during the digitising process. If you want to assign attribute data to them when mapping with OzGIS program, you have to provide the names that correspond to the object identifying numbers. You do this by choosing one of: DEFINE ZONE NAMES AND FEATURE CODES DEFINE LINE NAMES AND FEATURE CODES DEFINE POINT NAMES AND FEATURE CODES The identifying numbers are written to files, and can be read back in and changed. You can also assign one feature code to each polygon, line or point by either specifying them individually or assigning a default code. 23.10 Forming Polygons / checking --------------------------- The final product is a data file in standard OzGIS geographic format. This is produced by choosing GENERATE GEOGRAPHIC DATA FILE This process involves joining lines into polygons, if required, and outputting the topological structure to a file. Any names defined for zones, lines or points will be used. Errors are detected at this stage and messages are output to the OZGIS.OUT file. You need to use display and editing programs to fix any mistakes. You will find that careful analysis is sometimes required to discover digitising errors. 98 23.11 Editing Digitised Data ---------------------- You can choose EDIT DIGITISED DATA to display and modify the data. Options are: delete lines, points or zones plot lines, points or zones renumber intersections or zones split lines Change region displayed. 23.12 Variations ---------- Two extra digitising environments are available: 1. The table can be simulated by the PC screen and mouse/cursor. This can be used for very simple digitising, where your map has to be drawn on some clear medium. This also supports digitising boards that simulate a mouse. 2. Map overlays can be digitised by displaying a geographic file on the PC screen as the map to be digitised. Control points are not required as the transformation is known and a standard digitiser menu will be provided on the screen. 99 24. OzCatch RETAIL SITE CATCHMENTS (NOT AVAILABLE YET) ================================================== The OzCatch program enables catchments to be defined as contours around retail sites and the attribute data to be extracted from base zones. 24. 1 Introduction ------------ Modules have been developed for site selection on a VAX using RAMTEK display systems. This software has to be completely rewritten for the limited PC displays. It is uncertain when or if the software will be made available on the PC 24. 2 SITE CATCHMENTS ---------------- 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 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 - type of zones. A site analysis could be carried out as follows. 100 Phase 1 - Definition Each catchment file has to be defined. - A base-map geographic file of suitable size is displayed. - An old catchment file may be read in for modification. - Sites are defined by giving a name and location (cursor or typing lat long). Initial catchment contours are given as circles. - The results are stored as a catchment file. The zones list in the catchment file can now be output as anames file. The names file is passed to OzData, attribute data are retrieved for the site catchments, and some basic statistics calculated. On the basis of correlation coefficient and error levels for particular sites, the modifications for site catchments are decided. e.g. there may be 2 or 3 base maps for Melbourne and others for the country areas, each with different sites on them. Phase II - Modification of Catchments The site catchments (or positions) now have to be modified to obtain better agreement with known results. - The base map is displayed again. Other site catchment files and geographic overlays (e.g. roads) may also be displayed. Note that the base map could be changed. - the sites are modified. More contours may be added. Contours may be replaced with circles of different radii or a replacement digitised. - Zones lists are re-calculated. - The new sites are processed by OzData again, and the process repeated if necessary. For example, the base maps could change, say to go from postcodes to collection districts. Contours would change to get a better fit to the client's data. Phase III - Zones A base map is displayed and the contours overlayed. The pixels within each contour polygon are counted and from the total zone pixel counts and contour weights a list of zones and weights for each site is generated and stored in the catchment file. The user has to make sure that the base map extends past the catchment. Note that any type of zones can be used as the contours are stored as lat-long points. 101 Phase IV - Display Preparation A base map is displayed that is to be used for the final maps, and current catchment file displayed. All the catchment files are displayed - contours, symbols and site names. Symbols and names in the current catchment file are repositioned with the cursor if they conflict with those from other files. Lines are displayed between the symbol and true positions. A new catchment file is generated. An combine file is generated for retrieval of attribute data for all site names. A base map is displayed and the catchment files displayed that are to have the same symbol on the maps. A geographic file is generated for site symbol display. A geographic file to display the lines between the offset symbol locations and site locations is generated. This file also contains points for site name display. For example, a base map for the part of Victoria required would be subset from a Victorian postcode map. All the catchment files are displayed and names and symbols moved for the locations where there are two close sites. Phase V - Map Production A names file is generated from the combine file for all sites that are to be displayed. - Data are retrieved from OzData for the names file. - A map is displayed for either just sites, or sites on quantised map zones. If there are several sets of sites each file is added and possibly assigned to a different symbol. Note that symbol 1 is the top bit plane, symbol 2 the next down etc. Standard geographic overlays can be added from the geographic files that were generated; sites names, symbols, lines between symbol and true locations. - Other geographic overlays, diagrams etc are added. For example, a map could be displayed by using the Victorian postcode map as a base with postcode attributes, and displaying symbols at sites using attributes calculated by OzData. If potential sites are being evaluated, they would be in different geographic files and different symbols would be used. 102 A. DATA SOURCES ============ This appendix lists some of the major suppliers of map data which can be used with the OzGIS system. A. 1 General ------- Data are often available in different formats and at different prices. You need to be sure exactly what you want before ordering. If you are ordering Census boundary data you need to consider if you want to be able to amalgamate the polygons into bigger regions such as sales districts; if so you have to have segments. If you are ordering polygon formats (e.g. SAS) you will probably have to get them in a thinned form as otherwise the polygons may have too many vertices for the capacity of the OzGIS system under DOS. Thinned polygons are often cheaper. Generally, segments are preferable as they offer more capabilities, but they must not have too many vertices. Generally the system expects to be operating on geographic files that have the full zone-polygon-segments structure. Some operations are not available on files that were entered as polygons. A. 2 Australia --------- A. 2. 1 Australian Bureau of Statistics ------------------------------- The ABS collects and disseminates enormous volumes of statistics, some of which is available on floppy disk and CD ROM for mapping. The major data source is the Census of Population and Housing - by far the most extensive source of demographic data available in Australia. The ABS will supply data on floppy disk. Data output from the GeoStats product in LAMM format is supported. The ABS will supply boundary data for the 1991 Census. Arrangements have been made to obtain test data from the ABS so 1991 Census and boundary data will be supported when they become available in late 1992. Many publications describing the data are available. Contact: Information Services, Australian Bureau of Statistics, PO Box 10, Belconnen, ACT 2616. Phone (06) 252 5402, 252 6627, or 252 6007. 103 or any ABS state office. A. 2. 2 AUSLIG data ----------- The Australian Land Information Group in Canberra can supply the boundaries of the Collection Districts for the 1986 Census. Data are available for each state for:- - collection districts - postcodes - Local Government Areas - Statistical divisions - etc Ozenter can process the AUSLIG segments data to produce the OzGIS segments, which can then be formed into polygons with OzZone (to reflect the structure of the data e.g. which polygons are inside others). The data are extremely detailed, so large files are involved. Hence subsetting, segment joining and line simplification are usually used. All data are projection code 0 = latitude-longitude, units degrees. Make sure you get census boundaries in SEGMENTS format on floppy disk. Other map data are available, but need reformatting for use with OzGIS e.g. names file. AUSLIG is also selling postcode boundaries developed in collaboration with Telecom. Unfortunately, government policy of cost recovery means that AUSLIG data are expensive. Several publications are available. Contact: AUSLIG SALES (Digital Data), PO Box 2, Belconnen ACT 2616. Phone (06) 252 6389 Fax (06) 251 5446 A. 3 New Zealand ----------- The Department of Statistics have a product SAM (Socio-economic Area Mapping) and will supply data suitable for mapping on floppy disk. Contact their Information Consultancy Group first. Offices are in Auckland, Wellington, Christcurch and Dunedin. You should be able to obtain boundary data in a format supported within OzEnter (e.g. SAS, Gina). Population Census data and other attribute data are available in comma delimited formats. 104 A. 4 United Kingdom -------------- The various agencies are in the process of generating digitised boundary data, and there are some private efforts. Contact: The Office of Population Censuses and Surveys (OPCS), St Catherines House, 10 Kingsway London Phone 071 242 0262 or: Customer Services, General Register Office, Ladywell House, Edinburgh. Phone 031 334 0380 A. 5 USA Census Data --------------- The Census Bureau is the primary source of map data in the USA. They distribute boundary data as TIGER files and Census data as STF1A files. The data are distributed on CD-ROM so you need a drive or access to one. The Census Bureau has several offices throughout the USA. The 1990 Census TIGER/Line files are available on magnetic tape or tape cartridges (IBM 3480 compatible) from Customer Services Branch, Data User Services Division, Washington, DC 20233; (301) 763-4100. FAX: (301) 763-4794. The price is $200 for the first county in a state, plus $25 for each additional county in the same state ordered at the same time. The files also are available on CD-ROM disks. The price per disk is $250; most states fit on one disk. See the appendix for information on how to use TIGER and STF1A files. A. 6 Canada ------ Statistics Canada has not answered our letters or FAXes. A. 7 Others ------ Attemps to obtain other data from other suppliers has so far failed. The best we get is a heap of glossies. Questions we ask in our letters are ignored. Requests for test data are either greeted with paranoia or are ignored. Most suppliers also sell mapping software, so it is not in their interest 105 to encourage a competitor selling at a fraction of the price. It also does not look good when they are selling data at many times the price of the software. You will find that you can usually buy map data in one of the formats supported by OzGIS. 106 B. MAP DATA FORMATS ================ This appendix describes the data formats supported by the OzEnter program. You obtain your data on a file in a format supported by the OzEnter program, and use the appropriate option to read that file and create an OzGIS file that can be used for mapping. B. 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 OzEnter program. If not, data will have to be reformatted into one of the system formats before use. B. 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. - 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. 107 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. B. 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 108 B. 4 Format of attribute files ------------------------- B. 4. 1 Preprocessing ------------- Attribute data are often obtained from Census Bureaux. These data are seldom what is required, so will need processing by OzData 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. B. 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 109 B. 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 B. 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 B. 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 110 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 B. 4. 6 Spreadsheet data formats ------------------------ 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. 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 B. 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" 111 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 to OzEnter. The first is the format file, the second the Atlas data file. The format file is handled as a parameter file within the OzEnter program 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). B. 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 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) 112 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 B. 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 value is the item (zone,line or site) name and there follows one number for each attribute. The comma delimited form is seriously deficient in that it contains no attribute descriptions. Processing this format would require asking the user to type in the description for each attribute which is time consuming and there is always the danger that an attribute could be incorrectly labelled. Either: read the data into a spreadsheet Or: convert into LAMM or ATLAS format with a word processor. The file DEMOCOMD.DAT looks like: 2727400,115,114,105,6 2727800,77,75,63,29 PHRED,85,81,66,36 NEW YORK,5,6,3,3 2728200,27,27,21,12 2728300,74,72,63,34 . . . . 2739100,13,12,12,5 2739200,2,0,3,1 113 B. 4.10 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. 114 B. 5 Standard OzGIS formats for geographic files ------------------------------------------- B. 5. 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 OzZone program. Coordinates are usually given either in degrees (for lat,long) or in metres / feet for UTM. B. 5. 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. 115 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. B. 5. 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. B. 5. 4 Comment Record -------------- 80 byte comment describing the data B. 5. 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) 116 B. 5. 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 B. 5. 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 Region Record: 4x10 real line limits (window) X minimum, X-maximum, Y-minimum, Y-maximum) 117 Segments Records: 8x10 integer the identifying numbers of the line segments. B. 5. 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. B. 5. 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 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 118 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 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) B. 5.10 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. 119 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. B. 5.11 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 using OzEnter, then excessive vertices discarded (thinned) using OzData, and then the full zone / polygon/ line segment / centroids structure built using OzZone 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 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 4 119.00 513.00 114.00 518.00 109.00 517.00 104.00 516.00 120 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 B. 5.12 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 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 11 121 102.00 503.00 103.00 509.00 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 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 2 102.00 503.00 103.00 509.00 122 B. 5.13 Sample lines geographic file DEMOLINES.DAT ------------------------------------------ A lines structure is used for line data that is to be displayed for attribute data: COMMENT LINE FOR TEST 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 3 103.50 114.50 503.50 513.50 125 107 143 ROAD 2 3 103.50 110.50 503.50 513.50 263 281 125 ROAD 4 3 104.50 119.50 513.50 517.50 205 227 187 SEGMENTS 10 107ROAD 1 OUTSIDE 2 103.50 503.50 114.50 503.50 125ROAD 2 ROAD 1 2 103.50 503.50 110.50 513.50 143ROAD 1 ROAD 3 2 114.50 503.50 110.50 513.50 161ROAD 3 OUTSIDE 6 114.50 503.50 115.50 505.50 116.50 507.50 117.50 509.50 118.50 511.50 119.50 513.50 187ROAD 2 ROAD 3 2 110.50 513.50 119.50 513.50 205ROAD 2 OUTSIDE 4 119.50 513.50 114.50 517.50 109.50 517.50 104.50 516.50 227ROAD 2 OUTSIDE 2 104.50 516.50 110.50 513.50 245SURPLUS SURPLUS 2 119.50 513.50 121.50 506.50 263OUTSIDE ROAD 2 2 103.50 509.50 110.50 513.50 281OUTSIDE ROAD 2 2 103.50 503.50 103.50 509.50 B. 5.14 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). 123 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 124 B. 6 Format of polygon geographic files ---------------------------------- B. 6. 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. B. 6. 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 125 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 . . . . . B. 6. 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 126 10 byte zone name 10 real X coordinate 10 real Y coordinate 10 integer Polygon number within zone B. 6. 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 9.0 127 B. 7 GIS / common geographic file formats ------------------------------------ B. 7. 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 OzZone to build polygons and then through OzData 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 B. 7. 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 adding prefixes. Point names are POINT + 5 digit number, zone names are AREA + 6 digit zero filled number e.g. AREA000001 AREA000630 POINT00004 POINT00234 128 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. 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 OzZone program. 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. 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. 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 1 129 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 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 B. 7. 3 Gina format ----------- The standard interchange format for GeoVision GIS is Gina. OzEnter processes some of the file. 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 - OzZone has to be used to generate the zones / polygons. 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 130 coord-sys rect feet extent -12000, -8000, 12000, 8000 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 920 131 attr 2-story 10875 feat 22 1100 5 2 p xy 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 B. 7. 4 ANSII standard -------------- The new standard format for interchange will be supported when test data become available. B. 7. 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: 132 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 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. B. 7. 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 OzData, 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). 133 B. 7. 7 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: "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 134 . . "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: 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. 135 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 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 2,2 136 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. B. 7. 8 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 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 137 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 . . . . . . . . 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 . . . 138 B. 8 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 B. 8. 1 Sample names file DEMOATTR.DAT ------------------------------ DEMONAMES.DAT - NAMES FILE ZONE 1 ZONE 2 ZONE 4 B. 9 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 139 salmon .4471 .5020 .9804 steelblue .7059 .5098 .2745 turquoise .8157 .8784 .2510 yellowgreen .1961 .8039 .6039 B.10 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) B.10. 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 B.11 Format of presentation files ---------------------------- Presentation files give a set of saved map files that are to be referenced 140 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 B.11. 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 B.12 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 141 B.12. 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 B.13 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. 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 142 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 = hatch 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 Colour table records: 10 real blue value (0.0 - 1.0) for colour table 10 real green 10 real red Hatch definition record: 143 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: on display devices hardware text of known size will be used. Fonts are available for use on the screen, but are more usually used for output on plotters. The following fonts are available: 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 144 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 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 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: 145 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 4 input of values 5 error messages The 5 menu records use internal text numbers 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 146 The system by passes the colour index and style index when operating in fast interactive code and accesses the LUT directly. 147 C. 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. C. 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 OzEnter program 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 corrected when the WINDOWS3.1 version becomes available as it will use 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 OzEnter menus. 148 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, so OzData program 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 with OzData to reduce their size and speed up display. The polygons have to be built with OzZone to produce the final geographic file. Finally the data are mapped with OzCensus (simple maps) or OzGIS. Note that the number of tract/BNAs will often be under the magic 240 zone limit, so fast interacive mapping will be available on 256 colour super VGA systems if 16 colour device files are used. Otherwise you will have to keep redrawing the maps every time something changes. 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. C. 2 Documentation ------------- Extensive documentation is available from the Census Bureau and on the CD-ROMs. Some of that documentation is reproduced here. C. 3 OzGIS Processing of TIGER data ------------------------------ You enter TIGER data into OzGIS with the OzEnter program. Select INPUT GEOGRAPHIC FILES from the top menu and then INPUT 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 OzZone program has to be used to build the polygons. 149 The option SELECT LINES BY FEATURE CODES will also be used often to extract line overlay data such as roads. 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 OzEnter 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. 150 C. 4 Processing STF1A data --------------------- US Census data STF1A files can be entered into the system with the OzEnter program by choosing INPUT ATTRIBUTE FILES from the top menu and then one of: INPUT USA CENSUS STF 1A FILES FOR TRACT/BNA INPUT USA CENSUS STF 1A FILES FOR BLOCK GROUPS 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. 151 C. 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 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 . . . . . C. 6 Example ------- You should have looked at the early chapters on using OzCensus and OzEnter 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 . 152 . 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 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. Type OZENTER to start the program A menu appears: TUTORIALS & SYSTEM INFORMATION INPUT GEOGRAPHIC FILES INPUT ATTRIBUTE FILES INPUT A NAMES FILE INPUT A COMBINE FILE INPUT A DEVICE FILE INPUT A MARKER FILE select the option to INPUT ATTRIBUTE FILES A new menu appears: INPUT A STANDARD FORMAT ATTRIBUTE FILE INPUT A LOTUS 1-2-3 FORMAT ATTRIBUTE FILE INPUT A DATABASE (SIMPLE) FORMAT ATTRIBUTE FILE INPUT A LAMM FORMAT ATTRIBUTE FILE INPUT USA CENSUS STF 1A FILES FOR TRACT/BNA INPUT USA CENSUS STF 1A FILES FOR BLOCK GROUPS INPUT ATLAS DATA FILES 153 Obviously you now select: INPUT 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. Type F10 to 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 OzEnter run to find the variable numbers. Suppose it looks like: 1 TOTAL PERSONS . . . 108 12 AND 13 YEARS 109 14 YEARS 110 15 YEARS . 154 . . The new variable is the sum of the three age variables, divided by the total. Now type OZDATA to execute the data preparation program. The menu looks like: PROCESS ATTRIBUTE FILES PROCESS GEOGRAPHIC FILES PROCESS NAMES FILES OUTPUT EXTERNAL DATA FILES 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, and then type F10 to quit the program. 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 Type OZENTER to start the program. select INPUT GEOGRAPHIC FILES and then INPUT A TIGER FORMAT GEOGRAPHIC FILE. The TIGER menu is: TRACTS / BNA BLOCK GROUPS BLOCKS ZIP CODES (IF PRESENT) 155 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. 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. type F10 to exit. 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. 156 Simplification is an option in the OzData program which reads a geographic file and outputs a new one where the line segments have less points. So, type OZDATA to execute the program. 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. type F10 to exit. 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. Type OZZONE to run the program. 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!) type F10 to quit. 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 157 Step6: Display simple maps -------------------------- You can start by displaying some simple maps with the OzCensus program. Type OZCENSUS to execute the mapping program. 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. If you use an option such as changing the displayed attribute you may have to type F3 to cause the new map to be displayed. Refer to the chapter at the front of the manual on using OzCensus if you have not already looked at the example there. type F10 to exit. 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 158 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 OzCensus. The difference is that you now have many more options for mapping. The main menu is: CHANGE ATTRIBUTES DEFINE QUANTISATION CHANGE DISPLAY FEATURES DEFINE GEOGRAPHIC OVERLAYS DEFINE MAP REGIONS ANALYSE MAP DATA SAVE DISPLAY FEATURES 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 DEFINE MAP REGIONS. 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. Type F3 to regenerate the map in necessary. 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. 159 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 OzData 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 may have to type F3 to regenerate the map i.e. to cause the changes to appear. 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. 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. type F10 to exit. 160 C. 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 OzData. These names are unique only within a state. C. 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). C. 9 STF1A Geographic areas ---------------------- C. 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, 161 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. C. 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. C. 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 162 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. C. 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. C. 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 163 "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. C. 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 C. 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. 164 C.10 The STF1A file -------------- C.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 165 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. C.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 C.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). C.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. 166 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 167 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. C.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. 168 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. 169 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. C.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 170 110 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, 171 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 172 232 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 173 453 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 174 660 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 175 D. 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. D. 1 Configuring for a Super VGA --------------------------- INTERACTER supports 5 non-standard screen modes numbered 9 to 13 which can be activated by inserting suitable 'MODEnn' keywords in the INTERACTER initialisation file. The INTERACT.INI file contains some examples which contain suitable initialisation file MODEnn entries for various combinations of video board and display monitor. The supported non-standard screen modes are as follows INTERACTER Mode Type Mode Number ----------- --------- 9 640x400 'Olivetti' monochrome graphics 10 132x25 16 colour text 11 800x600 16 colour 'Super VGA' graphics 12 256 colour 'Super VGA' graphics 13 256 colour 'Super VGA' graphics Notes : (1) The dimensions of mode numbers 12 and 13 are definable as part of the MODEnn keyword. By default they are 640x480 and 800x600 modes. (2) 800x600 and 1024x768 modes will require a multisync or Super-VGA type monitor. On certain boards, 132 column mode also requires such a monitor. Be sure to use a suitable monitor/adapter combination. (3) The precise mode numbers used by particular video board manufacturers can vary. Users should check the documentation supplied with their video board before including the supplied example MODEnn entries in their INTERACTER initialisation file. Initialisation entries can be found for following: Ahead B chipset ATI VGA Wonder chipset Chips & Technology chipset Everex chipset Oak Technology chipset Olivetti M24/M28/M300, AT&T 6300, Compaq Portable Paradise chipset (inc. Compaq, Dell, HP D1180A, AST VGA's)) Toshiba 3100 + Gas plasma screen Trident chipset TsengLabs ET3000 chipset TsengLabs ET4000 chipset 176 VAXmate II Video 7 chipset By default, mode numbers 12 & 13 are 640x480 and 800x600 256 colour Super VGA modes using the TsengLabs ET3000 chipset. However the precise dimensions of these modes can now be specified using the MODE12 and MODE13 initialisation keywords which now take up to 7 parameters : MODE12 = ax bx cx dx chipset width height MODE13 = ax bx cx dx chipset width height ax bx cx dx = Interrupt 10h mode selection register values, as before chipset = VGA chipset number : 0 = Tseng Labs ET3000 (default) 5 = ATI 1 = Tseng Labs ET4000 6 = Trident 2 = Paradise 7 = Chips & Technology 3 = Video 7 8 = Ahead B 4 = Everex 9 = Oak Technology width = screen mode width in pixels (default = 640 in mode 12 or 800 in mode 13) height = screen mode height in pixels (default = 480 in mode 12 or 600 in mode 13) Any trailing values which are omitted take the default values indicated. Available modes on the supported chipsets include : Chipset Chipset 640x350 640x400 640x480 800x600 1024x768 Number Tseng 3000 0 y y y Tseng 4000 1 y y y y y Paradise 2 y y Video 7 3 y y y Everex 4 y y y y ATI 5 y y y Trident 6 y y y y Chips & Tech 7 y y y Ahead B 8 y y y Oak 9 y y The precise combination of modes available on any given board varies according to the manufacturer and the amount of video RAM available. The 640x480 and 800x600 modes require 512k and the 1024x768 mode requires 1 megabyte. Here are some examples of suitable initialisation file keywords VGA board based on the Tseng Labs ET3000 chipset : MODE12 = 46 MODE13 = 48 VGA board based on the Paradise chipset : MODE12 = 94 0 0 0 2 640 400 MODE13 = 95 0 0 0 2 640 480 VGA board based on the Video 7 chipset : MODE12 = 28421 103 0 0 3 MODE13 = 28421 105 0 0 3 177 VGA board based on the Everex chipset : MODE12 = 112 19 0 0 4 640 350 MODE13 = 112 20 0 0 4 640 400 The number of text columns and rows available in modes 12 and 13 varies according to the pixel dimensions : Columns = mode_width/8 Rows = mode_height/14 (if mode_height < 480) or mode_height/16 (if mode_height >=480) This gives the following text dimensions : 640x350 mode : 80 columns x 25 rows 640x400 mode : 80 columns x 28 rows 640x480 mode : 80 columns x 30 rows 800x600 mode : 100 columns x 37 rows 1024x768 mode : 128 columns x 48 rows - Since most Microsoft compatible mouse drivers do not support a mouse cursor in non-standard PC graphics modes, an option has been added to the MODEnn initialisation file keyword which tells INTERACTER to display it's own cross-hair cursor in such modes. Simply place a single letter 'C' (upper or lower case) at the very end of the record containing the MODEnn keyword to cause INTERACTER to provide a mouse cursor in that mode. MODE9 = 64 C MODE11 = 88 C MODE12 = 94 0 0 0 2 640 400 c MODE13 = 95 0 0 0 2 640 480 c EXAMPLE................ Here is the configuration file for a 1Mbyte Trident board (1024 x 768 x 256) using a mouse and saving screens on disk. DISPLAY = 10 CHARSET = c:\ozgis\standard.chr COLUMNS = 80 TEMPMENU = \ozgis\menu.tmp TEMPWINDOW = \ozgis\window.tmp mode13 = 98 0 0 0 6 1024 768 C D. 2 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 178 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]. 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 179 For example, 9600 baud, no parity, 1 stop bit, 8 bits is 110 00 0 11 = C3 hex = 195 decimal D. 3 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: 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] | 180 | 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. 181 E. 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. 182 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 183 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, 184 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 185 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 186 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 187 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 188 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. 189 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. 190 F. SYSTEM LIMITS ============= The OzGIS system has a standard set of limits to various maximum counts. These correspond to array sizes. The limited memory on the PC makes these limits quite small under DOS. When the WINDOWS version is available these limits should be much larger. The standard limits are:- 500 max no displayed zones+sites+lines 500 max no values in attribute file (zones,sites,lines) 10 max no map regions 10 max no quantised zone geog files 10 max no quantised site geog files 10 max no quantised line geog files 10 max no line overlays 10 max no polygon underlays 10 max no marker overlays 10 max no name overlays 20 max no test strings displayed 50 max no polygons in a zone 499 max no segments in a polygon 100 max no segments in a line 256 max no vertices in a segment 500 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 2000 max no vertices in foreign segments data file 5000 max no zones that can be built from line segments 191 G. TROUBLE-SHOOTING ================ Many of the Oz programs use most of available memory in the 640K. If you have other programs loaded they man not run. This will often show up as errors when opening files. IO errors can be caused initially by not having buffers=20, files=20 set in config.sys. Another common cause is lack of disk space. Some processing uses a lot of disk space as scratch files. If you have trouble displaying maps then you probably have not configured the system properly. If you are using a super VGA get the system working in standard VGA mode first. Generally check the \ozgis\interact.ini file for the DISPLAY parameter for the monitor type (usually 10). Super VGA modes need the correct startup register values to be set. Edit the interact.ini file and throw away irrelevant parts. If you have trouble with the mouse in super VGA mode you may need the C parameter on the end of the mode command in the interact.ini file. Ensure that there are no comments following the C parameter. There have also been problems with incompatible mouse drivers; microsoft and Genius drivers are known to work. The mouse driver must be called MOUSE.COM. 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. 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. 192 H. 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. 193 I. FUTURE PLANS ============ The OzGIS system is undergoing constant development. Current plans are for: Support for 1991 Australian Census data (the first data should be available in August 92) Support for more data formats e.g. UK Census Support for formats of other PC mapping systems. Development of a WINDOWS 3.1 version. The primary reason is to enable the system to use extended memory to overcome some of the limitations in the DOS version e.g. it may be possible to display maps of 20,000 zones and handle polygons of up to (say) 10,000 vertices. Various minor enhancements. Spatial operations (polygon overlay) Digitising CONTENTS 1. OzGIS INTRODUCTION 4 1. 1 Programs 4 1. 2 Concepts 4 1. 3 Environment 5 2. SUMMARY 7 3. SYSTEM CONFIGURATION 10 3. 1 Introduction 10 3. 2 DOS system files 10 3. 3 Standard EGA and VGA boards 11 3. 4 Super VGA boards 12 3. 5 Maths Coprocessor 13 3. 6 Extra RAM 14 3. 7 Mouse 14 3. 8 Hardcopy configuration 14 3. 9 Digitiser 14 4. OzEnter DATA ENTRY 15 4. 1 Introduction 15 4. 2 Example of data entry 16 4. 3 Demonstration Files 18 4. 4 Example geographic and attribute data 18 4. 5 Example device files 19 4. 6 Marker data files 19 4. 7 Colour names data (no longer used) 19 5. BASIC CHOROPLETH MAPPING EXAMPLE 20 5. 1 OzCensus 20 5. 2 Example Choropleth Map 20 5. 3 Summary 23 6. INTERACTIVE USER INTERFACE TO OzGIS 24 6. 1 Menus 24 6. 1. 1 Menu format 24 6. 1. 2 Function keys 24 6. 1. 3 Stacking selections 25 6. 2 Questions 25 6. 3 Commands 26 6. 4 Graphic interaction 27 6. 5 Pop-up 27 6. 6 Print file 27 7. OzGIS FILES 28 7. 1 File Origins 28 7. 2 File types 29 7. 3 File Names 31 7. 4 Directories 31 8. DEVICE FILES 33 9. OzGIS MAP TYPES 36 9. 1 Map Types 36 9. 2 Attribute maps 36 9. 2. 1 Bivariate zones map Example 37 9. 2. 2 Zones & sites Example 37 9. 2. 3 Geographic (GIS) maps Example 38 9. 2. 4 Diagrams Example 40 9. 3 Presentations 41 9. 4 Saved-display files 41 9. 5 Time Lapse Display (not available) 41 10. ATTRIBUTE SELECTION 42 10. 1 Introduction 42 10. 2 Sequentially 42 10. 3 By number (position in file) 42 10. 4 By attribute description 42 10. 5 By arithmetic operation 42 10. 6 Zone/Site/Line names 43 11. QUANTISATION 44 11. 1 Introduction 44 11. 2 Quantisation Methods 45 11. 3 Quantisation Ranges 47 11. 4 Quantisation Lists 47 12. GEOGRAPHIC OVERLAYS 49 12. 1 Introduction 49 12. 2 USA Census / TIGER Overlays Example 50 13. DISPLAY CONTROL & MAP DESIGN 52 13. 1 Introduction 52 13. 2 Map Quantisation Legends 52 13. 3 Overlays (GIS) legends 54 13. 4 Other Legends 54 13. 5 Text 54 13. 6 Attribute Diagrams 54 13. 7 Displayed Colours (removed) 55 14. MAP REGIONS 57 14. 1 Introduction 57 14. 2 Regions 58 14. 3 Map List 59 14. 4 Quantised Zones 60 14. 5 Quantised lines 60 14. 6 Quantised sites 60 14. 7 Line Overlays 61 14. 8 Polygon underlays 61 14. 9 Marker Overlays 61 14.10 Name Overlays 61 14.11 Map Modification 61 15. MAP ANALYSIS 62 15. 1 Introduction 62 15. 2 Map Reports 62 15. 3 Attribute Data Statistics 62 15. 4 Map Interrogation 63 16. OzData DATA PREPARATION 64 16. 1 Introduction 64 16. 2 Attribute Files 64 16. 3 Geographic Files 65 16. 4 Names Files 66 16. 5 Output to Data Files 66 16. 6 Palette Files (Removed from system) 67 16. 7 Colour Names Files (Removed from system) 67 17. OzZone BUILDING ZONES FROM SEGMENTS 68 17. 1 Use 68 17. 2 Faulty Digitised Data 68 17. 3 Example 69 18. MAP PROJECTIONS 70 18. 1 Introduction 70 18. 2 Precision 70 18. 3 Latitude / longitude 70 18. 4 Projections 71 18. 5 Ellipsoids 71 18. 6 Use 72 18. 7 Example 72 19. OzMap HARDCOPY MAP PRODUCTION 73 19. 1 Overview 73 19. 2 Procedure 74 19. 3 OzMap Device files 74 19. 4 VECTOR Program 75 19. 5 OzMap Example 78 19. 6 Fitting Maps on the Page 79 20. OzTerr TERRITORY DEFINITION 81 21. ADDRESS MATCHING / GEOCODING 83 21. 1 Introduction 83 21. 2 Addresses 83 21. 3 Data entry 84 21. 4 Address Matching 84 21. 5 Matching Addresses 85 21. 6 Procedure 85 21. 7 Data 86 21. 8 Abbreviations parameter file 87 21. 9 Handling Errors 88 22. OzSpat SPATIAL OPERATIONS (being tested) 89 22. 1 Operations 89 22. 2 Feature codes 90 22. 3 Procedure 90 23. OzDigit DIGITISING (being ported from VAX) 92 23. 1 Introduction 92 23. 2 Configuration 92 23. 3 Files 92 23. 4 Preparation for Digitising 93 23. 5 Setting up the Menu 93 23. 6 Control points 95 23. 7 Digitising the Map 95 23. 8 Examining digitised data 97 23. 9 Giving Names and Feature codes 97 23.10 Forming Polygons / checking 97 23.11 Editing Digitised Data 98 23.12 Variations 98 24. OzCatch RETAIL SITE CATCHMENTS (NOT AVAILABLE YET) 99 24. 1 Introduction 99 24. 2 SITE CATCHMENTS 99 A. DATA SOURCES 102 A. 1 General 102 A. 2 Australia 102 A. 2. 1 Australian Bureau of Statistics 102 A. 2. 2 AUSLIG data 103 A. 3 New Zealand 103 A. 4 United Kingdom 104 A. 5 USA Census Data 104 A. 6 Canada 104 A. 7 Others 104 B. MAP DATA FORMATS 106 B. 1 Introduction 106 B. 2 OzGIS Data Formats 106 B. 3 Description of File Formats 107 B. 4 Format of attribute files 108 B. 4. 1 Preprocessing 108 B. 4. 2 OzGIS Standard Format 108 B. 4. 3 Sample attribute file DEMOATTR.DAT 109 B. 4. 4 Simple Attribute format (tabular database format) 109 B. 4. 5 Sample simple attribute file DEMOSASA.DAT 109 B. 4. 6 Spreadsheet data formats 110 B. 4. 7 ATLAS Data files 110 B. 4. 8 LAMM format 111 B. 4. 9 Comma delimited format 112 B. 4.10 Other attribute data formats 113 B. 5 Standard OzGIS formats for geographic files 114 B. 5. 1 General Information 114 B. 5. 2 Structure of data 114 B. 5. 3 Internal Data 115 B. 5. 4 Comment Record 115 B. 5. 5 Map Partition 115 B. 5. 6 Zones Partition 116 B. 5. 7 Line Partition 116 B. 5. 8 Polygons Partition 117 B. 5. 9 Segments Partition 117 B. 5.10 Points Partitions 118 B. 5.11 Sample boundaries geographic file DEMOZSEG.DAT 119 B. 5.12 Sample segments file with adddresses DEMOADDR.DAT 120 B. 5.13 Sample lines geographic file DEMOLINES.DAT 122 B. 5.14 Sample points geographic file DEMOPOINT.DAT 122 B. 6 Format of polygon geographic files 124 B. 6. 1 Standard (not implemented) 124 B. 6. 2 SAS Format Zone Files 124 B. 6. 3 Simple Format (old SAS) Zone Files 125 B. 6. 4 Sample simple zones data file DEMOSASG.DAT 126 B. 7 GIS / common geographic file formats 127 B. 7. 1 DIME format 127 B. 7. 2 DLG optional 3 format 127 B. 7. 3 Gina format 129 B. 7. 4 ANSII standard 131 B. 7. 5 SIF format (not available) 131 B. 7. 6 DXF format 132 B. 7. 7 ATLAS Export Format 133 B. 7. 8 MapInfo Data Interchange Format 136 B. 8 Format of names files 138 B. 8. 1 Sample names file DEMOATTR.DAT 138 B. 9 Format of colour names files (Removed from system) 138 B.10 Format of combine files 139 B.10. 1 Sample combine file DEMOCOMB.DAT 139 B.11 Format of presentation files 139 B.11. 1 Sample presentation file 140 B.12 Format of marker files 140 B.12. 1 Sample marker file SQUARE.DAT 141 B.13 Format of device files 141 C. USA Census data 147 C. 1 Overview 147 C. 2 Documentation 148 C. 3 OzGIS Processing of TIGER data 148 C. 4 Processing STF1A data 150 C. 5 The STF1A parameter file 151 C. 6 Example 151 C. 7 OzGIS Census Zone Names 160 C. 8 STF1A Census data 160 C. 9 STF1A Geographic areas 160 C. 9. 1 Blocks 160 C. 9. 2 Block Groups 161 C. 9. 3 Census tract and block numbering area 161 C. 9. 4 Census Tract 162 C. 9. 5 County 162 C. 9. 6 Hierarchical Presentation 163 C. 9. 7 Zip codes 163 C.10 The STF1A file 164 C.10. 1 File Segments 164 C.10. 2 Field Names In Numeric Data Tables 165 C.11 TIGER US Census Digital Map Data 165 C.12 TIGER files 165 C.13 TIGER Geographic Area Definitions 167 C.14 TIGER feature codes 169 D. CONFIGURING OZGIS 175 D. 1 Configuring for a Super VGA 175 D. 2 Hardcopy configuration for OzMap 177 D. 3 Plotter setup 179 E. GLOSSARY OF TERMS 181 F. SYSTEM LIMITS 190 G. TROUBLE-SHOOTING 191 H. REFERENCES 192 I. FUTURE PLANS 193