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GRAPHICA v2.5 A System for Drawing Scientific Graphs ▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀ User's Manual by Antonio Montes 22 February 1994 (C) Copyright 1992-94 Antonio Montes. Portions (C) Copyright 1992 Borland International. ▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀ If you like this program, you can send a contribution to the address near the end of this file. Contributors to the development of Graphica are entitled to mail support, a copy of the latest version, and 10 additional software fonts. Please tell me the version number of your copy of Graphica when you send in your contribution. My address can be found near the end of this file. ▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀ MANUAL SUMMARY ▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀ Chapter 1: INTRODUCTION Contains information concerning installation and hardware requirements. Chapter 2: GETTING STARTED Defines the fundamental elements common to all plots, defines the manual usage and presents a description of the command syntax. Chapter 3: TUTORIAL Takes the user through a series of short lessons to get familiar with Graphica. Chapter 4: COMMAND LIST Gives a list of all the commands understood by Graphica. BUG REPORTING CONTRIBUTIONS TABLE OF CONTENTS ▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀ Chapter 1. INTRODUCTION 1.1 Overview 1.2 Disclaimer 1.3 Files 1.4 Equipment Requirements 1.5 Installation Chapter 2 GETTING STARTED 2.1 Overview 2.3 Document Conventions 2.3 Starting Up and Exiting 2.4 For Beginners 2.5 Errors Chapter 3 TUTORIAL 3.1 Introduction 3.2 Entering Commands 3.3 Plotting Functions 3.4 Plotting Data 3.5 Plotting Data Files 3.6 Plotting Parametric Curves 3.7 Using Script Files 3.8 Multiple Graphs on one Page 3.9 Importing Graphica Plots into WordPerfect Chapter 4 COMMAND LIST Chapter 1 INTRODUCTION ▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀ 1.1 Overview ───────────── Graphica is a command-driven interactive graphics program for making presentation quality graphs on a computer. This two- dimensional data plotting system is designed specifically for scientific and engineering applications. Graphica is SHAREWARE, i.e. it's user-supported. Graphica is easy to use, interactive, and powerful. With Graphica, you can: o plot functions or data o evaluate and plot mathematical expressions o fit spline or polynomials to data o display and print a graph on hardcopy devices o export graphs to HPGL, LaserJet, PostScript, etc. o draw text in roman, greek and cyrillic fonts o get online help 1.2 Disclaimer ─────────────── The authors have made their best effort in producing this software, but hereby disclaim all warranties. The authors will not be liable for any damages arising from the use or misuse of Graphica. The person using the software bears all risk as to the quality and performance of the software. The program is provided as is. 1.3 Files ────────── Graphica consists of the following files: GRAPHICA.EXE main program (executable) GRAPHICA.FIL help file (text file-may be printed) YY*.BIN binary font files (anywhere in the DOS path) README.1ST quick instructions (this file) DOCS.ZIP archive containing: GRAPHICA.DOC short user's tutorial REGISTER.DOC contribution information ORDERFRM.DOC order form HISTORY.DOC log of latest changes and improvements SHAREWRE.DOC about shareware GRAPHICA.ICO icon you can use with Microsoft Windows EXAMPLES.ZIP another archive containing example: *.PLT script files *.DAT data files 1.4 Equipment Requirements ─────────────────────────── Graphica normally detects automatically what graphics monitor hardware is present in order to preview graphs. In general, you basically need the following items: Computer: IBM PC,XT,AT or compatibles Disk Drives: 2 floppy drives or 1 floppy drive/hard drive Memory: 640K Bytes Video Cards: CGA, EGA, VGA or compatible adapter Hercules Monochrome Adapter or compatible Hardcopy: - Plotters HP7475A or HPGL compatible - Printers Epson 80 and 100 series Panasonic 1080i or equivalent Other Output: PIC HPGL PostScript HP LaserJet II, 4 1.5 Installation ───────────────── There are no special installation requirements. The simplest procedure is to make a new directory on your hard disk, and to copy all of the files there. You may wish to put the Graphica directory on your path, or to copy the files to a RAM disk. Let's suppose you wish to install Graphica into a directory called GRAPH. To create the directory, simply do the following: C:\md graph C:\cd graph If you have changed your system prompt with $P$G (as part of your AUTOEXEC.BAT file, for example), the prompt should show: C:\GRAPH> Graphica should have been distributed as one file, called GRPHCAxx.ZIP or GRPHxx.ZIP, where xx is the version number. All files will have to be extracted with PKUNZIP or an equivalent program on the command line. Do: C:\GRAPH> pkunzip grphcaxx All the files will be put in this directory and now you are ready to start graphing. Chapter 2 GETTING STARTED ▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀ 2.1 Overview ───────────── Graphica is an interactive computer program which accepts English sentence specifications of graphs, and, from those specifications, produces publication quality pictures. This manual describes how to use Graphica. The specifications that the user provides are referred to as "commands" or "statements". Final graphs are of publication quality and may be fitted to pages with existing text thereby eliminating costly reproduc- tions (photocopying and reduction). The user operates the program through a set of problem oriented language (POL) commands. Each command consists of keywords and data values separated by blanks or commas. This requires minimum data input and enables simple and efficient graphing. For example, if the user enters: map x 0,10 y 0,100 Graphica determines that the user wants the x-axis range set from 0 to 10 and the y-axis range set from 0 to 100. The user must separate entities in a command with blanks or commas. In this manual, blanks are not explicitly indicated. Graphica capabilities include: - multiple curve plotting and graphs - axis drawing with labels and scaled divisions - log-log, semilog, probability and linear plots - graph titles and legends - lettering in five fonts and different sizes - hardware and software character generation - 3 units of measure (in, cm, mm) 2.3 Document Conventions ───────────────────────── Input to Graphica is in the form of a problem oriented language (POL) designed specifically for graphing purposes. The following is a description of the conventions used within the manual to explain Graphica commands. The appearance within a Graphica command of a descriptor of the form <integer> implies that the user is to enter an item of data within that position in the statement of the class described by the descriptor (in the above example, an integer). The command divisions x <integer> ,<integer> implies that the word divisions is to be followed by the word x and two integers such as 2 or 3, and that the statement entered by the user as input data should be of the form divisions x 2,2 The following are definitions of most of the descriptors used within the language. Those not described below are ex- plained when they first occur in the text. <integer> a series of digits optionally preceeded by a plus or a minus sign. Examples are 121, +300, -410. <real> a series of digits with a decimal point included, or a series of digits with a decimal point followed by an exponent indicating a power of 10. Real numbers may be optionally signed. Examples are 1.0, -2.5, 3.6E+10. <value> is either an integer or a real number. 'string' is any textual information enclosed within a pair of apostrophes (') or quotes ("). An example is 'Are you following this so far?' As noted above, input to Graphica is a series of English- like commands. Many of the words or phrases in these commands are optional and are permitted primarily for readability or are used to specify options within a command. The curly braces {} denote these optional items. Each command is entered on a new line. Commands can be entered in lower case, upper case, or both. Only the first significant characters of a command are needed. A line starting with a left square bracket [ or a # will be treated as a comment line. Also, anything after those two characters in a line will be treated as a comment (see section 5.5). Items such as <integer> shown in the command definitions must always be replaced by an integer. Undesignated items such as <minimum> , <maximum> , etc. can be replaced by either an integer or a real. For example, divisions x2 <integer> ,<integer> can be specified as div x2 3 2 whereas map x <minimum value> <maximum value> can be entered as map x 20 30 or map x 20.0 30.0 Sometimes keywords in a command line can be entered in any order (except the very first one, of course). For instance, plot add x connect y will plot the X/Y data connecting all points and adding symbols. In many commands, items may be repeated or more than one word is acceptable in a given position within a command. The choices are listed enclosed in curly brackets '{}'. For example, the command definition draw {x} {y} {x2} {y2} {mask} {reflect} indicates that the user may enter commands like draw x reflect y2 reflect draw x y draw y reflect x2 mask. Similarly, paper {size} <horizontal value> {by} <vertical value> can be written as paper size 11.0 by 8.5 pap 11.0 8.5 or paper 11 by 8.5 In order to be more descriptive within the command definitions, actual data items (items enclosed within '<> ') are sometimes described in terms of their physical meaning and followed by the type or class of data item which can be used in the command. For example, a command definition of the form load {from} {file} <filename> implies that the data item following the word input is the name of a file. For example, acceptable commands would be load myfile.p load from 'graph.dat' 2.3 Starting Up and Exiting ──────────────────────────── Graphica can be run from any directory as long as GRAPHICA.EXE is placed in the directory search path. To start the plotting system, simply type graphica at the DOS prompt: C:\graphica Graphica takes a few seconds to load into memory, and when the > prompt is displayed, the program is ready for your input. To exit, type quit or exit at the Graphica command level. > quit and you're back at the DOS prompt. 2.4 For Beginners ────────────────── For a quick demonstration of Graphica's main capabilities, run Graphica and then load some of the sample script files (*.PLT). For example, C:\GRAPH\graphica (press return) > load 'demo1' (press return) Alternatively, command-line arguments may be names of files containing Graphica commands. Then, for example, C:\GRAPH\graphica demo1 is another way of running this demonstration. 2.5 Errors ─────────── Error messages are self-explanatory. If an error is detected while parsing a command or a script file, Graphica will inform you with a beep and message. CHAPTER 3 TUTORIAL ▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀ 3.1 Introduction ───────────────── Welcome to the Graphica tutorial. A plot is a graphic image used to present information in a visual manner. The components of a graphic image are: lines, markers, text strings, polygons, etc. The basic ingredients of a plot are: a page, a subplot area and data points. The data points are plotted using symbols, characters or simple dots. Data points and curves are drawn or plotted on a grid space formed by Cartesian coordinate axes. The horizontal line is the x-axis and the vertical line, the y-axis. A graph is made with Graphica by either loading an existing script file from the disk, or by creating a new graph through the command line. This section explains how to create graphs. All commands may be abbreviated, as long as the abbreviation is not ambiguous. Any number of commands may appear on a line, separated by semicolons. A file is loaded with the load command. Commands may extend over several input lines, by ending each line but the last with a backslash (\). The backslash must be the last character on each line. The effect is as if the backslash and newline were not there. Commenting out a continued line comments out the entire command. 3.2 Entering Commands ────────────────────── For help on any topic, type help followed by the name of the topic at the > prompt. Let's get started. Let's assume that you have copied all the Graphica files in a directory called GRAPH. Start Graphica by entering graphica at the DOS prompt and pressing return: C:\GRAPH> graphica The screen will clear, there will be a brief notice and you'll be at the > prompt: > Now you are about to begin making scientific graphs. The plot command is the heart of Graphica. It is used to plot data, functions and datafiles. We will be using it a lot in the next few pages. Anytime you are ready to type in the next Graphica command and your screen shows a plot (in other words, you are in graphics mode), just press any key or start typing the command in. At the > prompt, you can always type show to have a look at what you have plotted on the screen so far. 3.3 Plotting Functions ─────────────────────── To plot a sine wave, enter the following command at the > prompt: > plot sin(x) Within a few seconds, a graph of sin(x) as a function of x will be plotted. Press any key and then enter: > draw x y The x and y axes will be drawn. The x axis will range from -10 to 10, since that is the default range. You can plot functions that have singularities. Graphica will try to choose the appropriate y scale. Enter: > clear to sort of clear your graphics slate. Then enter: > sampling 300 > plot tan(x) The sampling command simply tells Graphica that we would like to plot more points of the function that the default of 150. After that, the plot command plots the function. To draw the axes, do: > draw x y You can give a list of functions to plot all at once. Go ahead and clear everything by entering: > clear Then, map the x-axis with the following command: > map x 0 2*pi To actually plot the functions, enter: > plot sin(x), sin(2*x), sin(3*x) And to draw the axes: > draw x y Graphica always tries to plot functions as smooth curves. As a result, in places where your function wiggles a lot, you may adapt Graphica's sampling of your function to the form of the function (we did that by giving the sampling command at the beginning of this section.) Since Graphica can only sample your function at a limited number of points, it can sometimes miss features of the function. By increasing sampling, you can make Graphica sample your function at a larger number of points. Of course, the larger you set sampling to be, the longer it will take Graphica to plot any function, even a smooth one. The function sin(1/x) wiggles infinitely often when x is near zero. Graphica can never sample the infinite number that it would need to reproduce the function exactly. As a result, there are slight glitches in the plot. Go ahead and try it: > clear > map x -1,1 > plot sin(1/x) > draw x y Now you have seen how to plot functions. See section 5.1 for a more detailed explanation about mathematical expressions. 3.4 Plotting Data ────────────────── You may combine two Graphica commands, plot and data, to plot data points. For example: > clear > data data> 2 3 data> 5 4 data> 6 4 data> 7 5 data> 5 3 data> end > plot x y add > draw x y This sequence of commands will result in a simple graph with both axis autoscaled. See the map command for more details on how to change the x-axis scale in the plot. 3.5 Plotting Data Files ──────────────────────── Data may also be plotted by retrieving the information from a data file. There are a couple of ways of doing this. The first is by simply specifying: > clear > data 'bob.dat' where bob.dat contains 3 columns of numbers. To plot the data, you can do: > plot data which will plot the first 2 columns. To draw the axes: > draw x y Using the other method, you can plot a datafile directly: > clear > plot 'bob.dat' and now the axes: > draw x y The first method allows you to read in several columns of data and then choose which one will be plotted (see column in the reference section.) By default, specifying plot data simply plots the first two columns of data as x versus y. 3.6 Plotting Parametric Curves ─────────────────────────────── In a parametric plot, you give both the x and y coordinates of each point as a function of a third parameter, say t. Let us construct a parametric plot. In this example, the parametric curve made by taking the x coordinate of each point to be sin(t) and the y coordinate to be sin(2*t): > clear > parametric plot t 0,2*pi sin(t) sin(2*t) > draw x y 3.7 Using Script Files ─────────────────────── Every graph in this documentation can be readily reproduced from the script files provided in the Graphica package. A script file is simply a text file containing valid Graphica commands. The script file can be executed by the load or input command. The name of the input file must be enclosed in single or double quotes: > clear > load 'torp.plt' 3.8 Multiple Graphs on one Page ──────────────────────────────── With Graphica, you may plot as many graphs on one page as you wish by changing the subplot area. Try this: > clear > load 'rocha.plt' Several axes have been defined, x and y axes with labels, a y2 axis without labels, etc. The data shown is actual experimental data obtained by a doctoral student and the graph is part of his dissertation. You may now quit Graphica by typing exit at the > prompt. 3.9 Importing Graphica Plots into WordPerfect ────────────────────────────────────────────── This document was prepared using WordPerfect 5.1. The plots were produced with Graphica, exported using HPGL output and imported into WordPerfect. Once a graphic has been imported into WordPerfect, you can move it, scale it, rotate it, add captions, etc. Let's create a graph with Graphica and retrieve it into a WordPerfect document step by step. There is a file in your distribution disk called ris108.plt. Start Graphica: C:\GRAPH> graphica and load the script file: > load 'ris108.plt' The screen will clear and a plot will be drawn. In fact, this plot makes use of font 5 (complex cyrillic). The graph was created after one in a russian text dealing with petroleum chemistry (I thought it might draw your attention). Now press any key and enter: > dump hpgl 'ris108.hpg' The dump command will create a file called ris108.hpg containing HPGL commands. You may later send this file to a plotter or pull it into any of the many programs that accept HPGL commands. Now, exit Graphica by typing: > quit and start WordPerfect: C:\GRAPH> wp When the screen clears, do the following: 1) press Alt-F9 (for the graphics menu) 2) type 1 (for figure) 3) select 1 (for create) 4) select 1 (for filename) 5) enter ris108.hpg (to read the file in, no quotes) WordPerfect will retrieve the HPGL information into a graphic box immediately. You can edit the graph further within the graphics menu: 6) press 9 (for edit) or simply view the graph: 7) press F7 (to exit the graphics menu) 8) press shift-F7 (for print) 9) press 6 (for view document) and you have successfully imported a Graphica plot into a WordPerfect document. CHAPTER 4 COMMAND LIST ▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀ This chapter gives an alphabetical lookup for all the Graphica built-in commands. Here are all the supported commands: ARROW Plot an Arrow at the End of a Line AUDIT Set Command Trace AUTOSCALE Set Axis Autoscaling BACKGROUND Specify Background Color BEEP Turn beep on and off CHARACTER Set Character Attributes CHARACTER FONT Change the Character Font CHARACTER GAP Change the Character Gap CHARACTER RATIO Change the Character Ratio CHARACTER SIZE Change the Character Size CHARACTER SLANT Set the Character Slant CD Change the Working Directory CIRCLE Draw a Circle CLC Clear Text Screen CLEAR Erase Output Device COLUMN Assign Data Columns to Axes DATA Read Data from Terminal or a File DEL Delete a file DIGITIZE Establish an x-y position DIR List a directory DIVISIONS Set Number of Axis Divisions DRAW Draw an Axis DUMMY Specify Dummy Variable DUMP Generate Hardcopy Output ECHO Echo Typed Commands EXIT Exit Graphica EXPONENT Select Format in Log Labels FORMAT Specify Axis Label Formats FRAME Draw a Frame FUNCTIONS Show Functions GRID Draw a Grid HELP Display On-line Help LABEL Draw a Label LEGEND Draw a Legend LINE Draw a Line (absolute) LINETO Draw a Line (relative) LOAD Specify an Input File LOCATION Specify Type of x/y Position MAP Specify the Limits of an Axis MASK Mask a Rectangular Area MEMORY Give the Amount of Memory Left MOVETO Move to a Point NOBEEP Turn Beep Off NOBORDER Do Not Draw the Paper Outline NOLABEL Clear all Labels NOTITLE Clear all Titles ORIGIN Specify Axis Origin OUTPUT Specify Output Terminal PAPER SIZE Specify Paper Size PARAMETRIC PLOT Plot a Parametric Curve PAUSE Pause and/or Wait for User Response PEN Specify a Pen Parameter PLOT Plot a Datafile, Curve or Function PLOTTING SEQUENCE Select a Plotting Sequence POLYFIT Generate a Polynomial by Least Squares PWD Print Current Working Directory QUIT Exit Graphica RECTANGLE Draw a Rectangle SAMPLING Specify Sampling Rate SHADE Shade a Specified Set of Data SHELL Spawn a DOS Shell SHOW Show the Current Screen SMOOTH Draw a Smooth Curve Through Data SPLINE Fit Data to a Spline SUBPLOT AREA Specify Area Where Plot Will Go SUB/SUPERSCRIPT Set the Sub/Superscript Size SYMBOL Select a Plotting Symbol TERMINAL Specify Output Terminal Type TIC Specify Tic Mark Size and Direction TITLE Draw a Centered Axis Label TYPE Type a file UNIT Specify Drawing Units VIEW Move Paper to View Plotter Output WHAT Show *.plt Files in Current Directory WHO Show Variables X,Y,X2,Y2 Specify Axis Type X,Y,X2,Y2LABEL Draw a Centered Axis Label The file 'graphica.fil' is used by the program to give you online help. It is an ASCII file and may be printed. It contains detailed information about each of the above commands, their features and how to use them. The 'revisions' section (HELP REVISION) gives information on last minute command changes, additions and/or corrections. The help file will always contain the latest information available about all commands in the version of GRAPHICA you now have. BUG REPORTING ▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀ Graphica is under constant revision, updating and being given expanded capabilities. Prior to each release, I strive to verify new features and bug fixes through testing. However, as inevitably happens with any software, some bugs do survive and show up in user runs. Users can aid in the problem fixing process by following the guidelines below: a) Report any unusual messages, computed results, format overflows, etc. even though the program appears to have terminated normally. b) For any abnormal program termination, save the input file and all output obtained by running the program. Reported problems will be fixed as quickly as possible. In most instances, alternate methods or techniques of plot formulation and input are available to permit graphing despite the bug. All problems encountered with Graphica should be reported to the address below.