/usr/share/doc/libplplot11/examples/c/x17c.c is in libplplot-dev 5.9.9-2ubuntu2.
This file is owned by root:root, with mode 0o644.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 | // $Id: x17c.c 11289 2010-10-29 20:44:17Z airwin $
//
// Plots a simple stripchart with four pens.
//
#include "plcdemos.h"
#include <stdlib.h>
#ifdef PL_HAVE_UNISTD_H
# include <unistd.h>
#else
# ifdef PL_HAVE_POLL
# include <poll.h>
# endif
#endif
// Variables for holding error return info from PLplot
static PLINT pl_errcode;
static char errmsg[160];
//--------------------------------------------------------------------------
// main program
//--------------------------------------------------------------------------
int
main( int argc, const char *argv[] )
{
PLINT id1, n, autoy, acc, nsteps = 1000;
PLFLT y1, y2, y3, y4, ymin, ymax, xlab, ylab;
PLFLT t, tmin, tmax, tjump, dt, noise;
PLINT colbox, collab, colline[4], styline[4];
const char *legline[4];
// plplot initialization
// Parse and process command line arguments
(void) plparseopts( &argc, argv, PL_PARSE_FULL );
// If db is used the plot is much more smooth. However, because of the
// async X behaviour, one does not have a real-time scripcharter.
// This is now disabled since it does not significantly improve the
// performance on new machines and makes it difficult to use this
// example non-interactively since it requires an extra pleop call after
// each call to plstripa.
//
//plsetopt("db", "");
//plsetopt("np", "");
// User sets up plot completely except for window and data
// Eventually settings in place when strip chart is created will be
// remembered so that multiple strip charts can be used simultaneously.
//
// Specify some reasonable defaults for ymin and ymax
// The plot will grow automatically if needed (but not shrink)
ymin = -0.1;
ymax = 0.1;
// Specify initial tmin and tmax -- this determines length of window.
// Also specify maximum jump in t
// This can accomodate adaptive timesteps
tmin = 0.;
tmax = 10.;
tjump = 0.3; // percentage of plot to jump
// Axes options same as plbox.
// Only automatic tick generation and label placement allowed
// Eventually I'll make this fancier
colbox = 1;
collab = 3;
styline[0] = colline[0] = 2; // pens color and line style
styline[1] = colline[1] = 3;
styline[2] = colline[2] = 4;
styline[3] = colline[3] = 5;
legline[0] = "sum"; // pens legend
legline[1] = "sin";
legline[2] = "sin*noi";
legline[3] = "sin+noi";
xlab = 0.; ylab = 0.25; // legend position
autoy = 1; // autoscale y
acc = 1; // don't scrip, accumulate
// Initialize plplot
plinit();
pladv( 0 );
plvsta();
// Register our error variables with PLplot
// From here on, we're handling all errors here
plsError( &pl_errcode, errmsg );
plstripc( &id1, "bcnst", "bcnstv",
tmin, tmax, tjump, ymin, ymax,
xlab, ylab,
autoy, acc,
colbox, collab,
colline, styline, legline,
"t", "", "Strip chart demo" );
if ( pl_errcode )
{
fprintf( stderr, "%s\n", errmsg );
exit( 1 );
}
// Let plplot handle errors from here on
plsError( NULL, NULL );
autoy = 0; // autoscale y
acc = 1; // accumulate
// This is to represent a loop over time
// Let's try a random walk process
y1 = y2 = y3 = y4 = 0.0;
dt = 0.1;
for ( n = 0; n < nsteps; n++ )
{
#ifdef PL_HAVE_USLEEP
usleep( 10000 ); // wait a little (10 ms) to simulate time elapsing
#else
# ifdef PL_HAVE_POLL
poll( 0, 0, 10 );
# else
{ int i; for ( i = 0; i < 1000000; i++ )
;
}
# endif
#endif
t = (double) n * dt;
noise = plrandd() - 0.5;
y1 = y1 + noise;
y2 = sin( t * M_PI / 18. );
y3 = y2 * noise;
y4 = y2 + noise / 3.;
// There is no need for all pens to have the same number of
// points or beeing equally time spaced.
if ( n % 2 )
plstripa( id1, 0, t, y1 );
if ( n % 3 )
plstripa( id1, 1, t, y2 );
if ( n % 4 )
plstripa( id1, 2, t, y3 );
if ( n % 5 )
plstripa( id1, 3, t, y4 );
// needed if using double buffering (-db on command line)
//pleop();
}
// Destroy strip chart and it's memory
plstripd( id1 );
plend();
exit( 0 );
}
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