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Text File | 1987-08-25 | 9.6 KB | 240 lines

NAME graph - plot a tabulated function SYNOPSIS graph [file file file] [options] DESCRIPTION Graph takes pairs of points (two numbers per line) from the given file (or standard input) as x- and y- values and plots them on the screen, connected by straight lines. A string surrounded by quotes "..." may follow a pair of points, and will be displayed starting at that point. The program draws axes with convenient labels (integers times powers of 1000), plots the data, waits for a keypress, then resets the screen parameters and clears the screen before exiting. If data is taken from standard input (possibly redirected) the key pressed must be a carriage return. If graph is interrupted with a control-C, it may leave the display in a nonstandard mode. This can sometimes be fixed by running graph a second time and letting it exit normally. Blank lines and lines beginning with ';' are ignored. More than one input file can be specified. All the data will be read before scaling parameters are calculated. The plot will be "broken" at the end of each file. That is, there will be no line connecting the last point of the first file with the first point of the second file. Similarly, if a line starts with a null byte (that is, if a line feed is followed by a null) the plot will be broken. Separate curves may also be delimited with labels (see the -b switch). The -m switch can be used to select the line style or marker style for each curve. If both markers and connecting lines are wanted, read the data file twice and specify different styles. For example, graph gamma gamma -m 1 -30 would give red squares connected by white solid lines. VERSIONS Graph is available in several versions. When necessary for configuration control, these versions are given different file names (see FILES section below). It is suggested that the "normal" version for a given computer be renamed GRAPH for simplicity. Two measures are taken to ensure no damage is done. First, any version of graph can be executed with a question mark as the only parameter: GRAPH ? It will then print a help screen which indicates the hardware it supports, and exit immediately. Second, graph tests that the hardware it needs is present before using it (except for the plotter and laser printer versions). The test is a permissive one, so that "clones" are likely to work. However, it can be fooled. For example, the Paradise EGA Autoswitch video card can emulate the Hercules monochrome graphics card, but only when connected to a monochrome monitor. If the Hercules version of graph is used with this card and an EGA color monitor, nothing is displayed. The following modes are supported on the IBM CGA: The mode is specified by setting the environment variable GRAPHICS before running graph: SET GRAPHICS=4 ; 200*320 color mode SET GRAPHICS=5 ; 200*320 grey scale mode SET GRAPHICS=6 ; 200*640 monochrome mode (the default) The terminology above is IBM's, but note that a color monitor connected to the 15 pin connector on the IBM color graphics adaptor will display color if the graphics mode is set to either 4 or 5. A composite color monitor connected to the RCA jack will display color only in mode 4. The IBM Enhanced Graphics Adaptor (EGA) is supported in mode 16 (350*640 color). At least 128K of memory is assumed, so that 16 colors are supported. If only 64K is installed, graph should still work but only 4 colors will be displayed. Only one page is used. The Hercules monochrome graphics card is supported in its graphics mode (naturally). Only page 0 (memory addresses b0000-b7fff) is used, so another video adaptor which is mapped into memory above b8000 (such as an IBM CGA) can also be present. The card is left in mode HALF (page 1 disabled). Similarly, these modes are supported on the Z-100: SET GRAPHICS=1 ; 225*640 mode (the default) SET GRAPHICS=2 ; 400*640 mode For the Houstin Instruments plotter, HP plotter, or LIPS-10 laser printer versions, the output port may be specified by setting an environment variable: SET plot_port=COM1 (the default) SET plot_port=COM2 SET plot_port=PRN Graph asks about several other options: pen speed, pen displacement before plotting begins, width and height of desired plotting area. OPTIONS Options can appear before, among, or after input file names provided a file name cannot be mistaken for the parameter of an option. -a [<step> [<start>]] Automatically generate abscissas. The first argument, if present, is the step between values (default 1). The second argument, if present, is the starting value (default 0, or first argument from -x switch). -b break (disconnect) the plot after each label. (See switch -m to plot the line segments with different linestyles. To break the plot without printing labels, use empty labels: "".) This option is set automatically if more than one input file or more than one linestyle is specified. -c <text> argument is default label for data points -e equal vertical and horizontal scales (same number of inches on the display per unit in problem space), so that circles don't look like elipses -g -g with no arguments eliminates the grid. -g <style> <tics> <width> First argument is grid style: -1 for tic marks outside the graph area, 0 for no grid, 1 for frame with tic marks inside (default), 2 for full grid. Second argument is approximate number of small tic marks per numeric label (1 to 10, default 5). Set <tics> to 1 to eliminate small tic marks. Third argument is width of grid lines (default 1). -l <text> next argument is label for graph (printed at top). If the label starts with a double quote it may contain spaces: -l "three cornered hat" -m <n1> <n2> <n3>... numeric arguments are linestyles for successive line segments (see switch -b). Each positive argument is a number of up to three digits WCS, where W is the linewidth (0-9, with 0 giving width 1), C is the color (with 0 being brightest), and S is linestyle (1-5, 1 for solid, 2 for dashed, 3 for dotted, etc.) If an argument is zero, the data points are plotted as dots not connected by lines. Similarly, a negative argument -CS generates a marker: C is the color S is the marker style (dot, box, cross, etc.) An argument can also include a repeat count, as in 3*45 or 4*-205. -n Omit numeric labels on axes. This uses more of the screen for the graph, therefore effectively increases resolution slightly. It may also be used when you want to make a hard copy and label it with a typewriter. -t Transpose x and y values before plotting (-x now refers to vertical axis). -x[l] [min [max [junk]]] If l is present, x axis is logrithmic. First argument, if present, is lower x limit. Second argument, if present, is upper x limit. A third numeric argument may be present but will be ignored. By default, these values are determined automatically. -y[l] [min [max [junk]]] Similarly for y axis -y[l]m [min [max [junk]]] -ya[p] [min [max [junk]]] -yp[p] [min [max [junk]]] Any of these signal that each line of the input contains the real and imaginary parts of a complex number (after the abscissa, unless -a is also used). An 'm' requests that the magnitude of the number (square root of sum of squares of real and imaginary parts) be plotted. 'p' or 'a' requests the phase (atan(imaginary part/real part), also known as the argument) be plotted. The signs of both parts are taken into account, so the phase ranges from -pi to +pi. If both real and imaginary parts are zero, the phase is arbitrarily assumed to be zero. An additional 'p' requests that the phase be divided by pi before plotting. -h <n> argument is the fraction of the vertical space to be used for the graph. -u <n> argument is the fraction of the vertical space to move up before plotting. -w <n> argument is the fraction of the horizontal space to be used for the graph (useful if screen dump routine doesn't dump the entire width of the screen). -r <n> argument is the fraction of the horizontal space to move right before plotting. FILES These are the currently available executable files: GRAPHPC.EXE IBM PC with CGA GRAPHEGA.EXE IBM PC with EGA GRAPHH.EXE IBM PC with Hercules monochrome graphics GRAPHZ.EXE Zenith Z-100 GRAPHHI.EXE Houstin Instruments DMP-29 plotter GRAPHHP.EXE HP 7470A plotter GRAPHLI.EXE CIE Laser Image Printing System, or LIPS 10 NOTES Graph is largely equivalent to the program of the same name on Unix, with the following exceptions: Data may come from one or more files rather than the standard input. Line segments that go out of bounds are windowed rather than being dropped. Graph may adjust the specified lower or upper limits (outwards) to give convenient axis labels. Steps along axes may not be specified. The screen is always cleared before plotting. The default grid type is frame with tics rather than full grid. Axes may not be reversed by specifying a lower limit greater than the upper limit. BUGS The screen is always cleared before a plot. AUTHOR Copyright (c) 1985, 1986, 1987 by James R. Van Zandt (jrv@mitre-bedford) 27 Spencer Dr., Nashua NH 03062, 603-888-2272. Resale forbidden, copying for personal use encouraged. Constructive comments welcome.