octave-plplot 5.10.0+dfsg-1 / usr / share / doc / libplplot12 / examples / octave / x01c.m

## Copyright (C) 1998, 1999, 2000 Joao Cardoso.
##
## This program is free software; you can redistribute it and/or modify it
## under the terms of the GNU General Public License as published by the
## Free Software Foundation; either version 2 of the License, or (at your
## option) any later version.
##
## This program is distributed in the hope that it will be useful, but
## WITHOUT ANY WARRANTY; without even the implied warranty of
## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
## General Public License for more details.
##
## This file is part of plplot_octave.
## It is based on the corresponding demo function of PLplot.

# Simple line plot and multiple windows demo.

1;

function ix01c(strm)

  # Redirect output to file if required
  if (nargin == 0)
    strm = stdout;
  endif

  ## plplot initialization */

  ## Parse and process command line arguments */

  ##    plMergeOpts(options, "x01c options", notes);
  ##    plparseopts(&argc, argv, PL_PARSE_FULL);

  ## Get version number, just for kicks */

  ver=plgver';
  fprintf(strm,"PLplot library version: %s\n", ver);

  ## Initialize plplot */
  ## Divide page into 2x2 plots unless user overrides */
  plstar(2,2);

  ## Set up the data */
  ## Original case */

  xscale = 6.;
  yscale = 1.;
  xoff = 0.;
  yoff = 0.;

  ## Do a plot */

  plot1(xscale, yscale, xoff, yoff);

  ## Set up the data */

  xscale = 1.;
  yscale = 0.0014;
  yoff = 0.0185;

  ## Do a plot */

  digmax = 5;
  plsyax(digmax, 0);

  plot1(xscale, yscale, xoff, yoff);

  plot2;

  plot3;

  ## Let's get some user input */

  ## the "gin" structure is as follows:
				#
  ## int state;     /* key or button mask */
  ## int keysym;    /* key selected */
  ## int button;    /* mouse button selected */
  ## char string; 	 /* translated string */
  ## int pX, pY;    /* absolute device coordinates of pointer */
  ## float dX, dY;  /* relative device coordinates of pointer */
  ## float wX, wY;  /* world coordinates of pointer */

  if (!exist("file") || (exist("file") && isempty(file)))
    printf("\n\nYou are in Locate mode. Click any mouse button or press any key\n\
and the current cursor position will be printed.\n\
Please keep <NumLock> and <CapsLock> off.\n\
Terminate locate mode with the <Enter> key.\n\
Finish the plot with the <Enter> or <ESC> key or the 3d mouse button\n");

    fflush(stdout);

    while(1)

      [status, mod, keysym, button, string, pX, pY, dX, dY, wX, wY, swin] = plGetCursor;

      if (keysym == hex2dec("0D")); break; endif
      
      if (status != 0)
	printf("wx=%.3f wy=%.3f dx=%.3f dy=%.3f c=0x%02x str=%s mb=%d mod=%0x swin=%d\n", ...
	       wX, wY, dX, dY, keysym, string, button, mod, swin);
      else
        break;       
      endif

      fflush(stdout);
    endwhile
  endif
  ## Don't forget to call plend1  to finish off! */

  plend1();

endfunction

function plot1(xscale, yscale, xoff, yoff)

  m=60;
  i=1:m;
  x = xoff + xscale * i / m;
  y = yoff + yscale * (x.^2.);

  xmin = min(x);
  xmax = max(x);
  ymin = min(y);
  ymax = max(y);

  i=0:5;
  xs = x(i * 10 + 4);
  ys = y(i * 10 + 4);

  ## Set up the viewport and window using PLENV. The range in X is 
  ## * 0.0 to 6.0, and the range in Y is 0.0 to 30.0. The axes are 
  ## * scaled separately (just = 0), and we just draw a labelled 
  ## * box (axis = 0). 

  plcol0(1);
  plenv(xmin, xmax, ymin, ymax, 0, 0);
  plcol0(2);
  pllab("(x)", "(y)", "#frPLplot Example 1 - y=x#u2");

  ## Plot the data points */

  plcol0(4);
  plpoin(xs', ys', 9);

  ## Draw the line through the data */

  plcol0(3);
  plline(x', y');

endfunction

function plot2 

  ## Set up the viewport and window using PLENV. The range in X is -2.0 to
  ## * 10.0, and the range in Y is -0.4 to 2.0. The axes are scaled separately
  ## * (just = 0), and we draw a box with axes (axis = 1). 

  plcol0(1);
  plenv(-2.0, 10.0, -0.4, 1.2, 0, 1);
  plcol0(2);
  pllab("(x)", "sin(x)/x", "#frPLplot Example 1 - Sinc Function");

  ## Fill up the arrays */

  i=0:99;
  x = (i - 19.0) / 6.0;
  y = sin(x) ./ x;
  y(x==0) = 1;
  
  ## Draw the line */

  plcol0(3);
  plwidth(2);
  plline(x', y');
  plwidth(1);

endfunction

function plot3 

  space0 = []; mark0 = []; space1 = [1500]; mark1 = [1500];

  ## For the final graph we wish to override the default tick intervals, and
  ## * so do not use plenv .

  pladv(0);

  ## Use standard viewport, and define X range from 0 to 360 degrees, Y range
  ## * from -1.2 to 1.2. 

  plvsta;
  plwind(0.0, 360.0, -1.2, 1.2);

  ## Draw a box with ticks spaced 60 degrees apart in X, and 0.2 in Y. */

  plcol0(1);
  plbox("bcnst", 60.0, 2, "bcnstv", 0.2, 2);

  ## Superimpose a dashed line grid, with 1.5 mm marks and spaces. 

  plstyl(mark1, space1);
  plcol0(2);
  plbox("g", 30.0, 0, "g", 0.2, 0);
  plstyl(mark0, space0);

  plcol0(3);
  pllab("Angle (degrees)", "sine", "#frPLplot Example 1 - Sine function");

  i=0:100;
  x = 3.6 * i;
  y = sin(x * pi / 180.0);

  plcol0(4);
  plline(x', y');
  
endfunction

if (exist("strm","var"))
  ix01c(strm)
else
  ix01c()
endif