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//--------------------------------------------------------------------------
// $Id: x16.java 11301 2010-11-02 17:21:08Z airwin $
//--------------------------------------------------------------------------
//--------------------------------------------------------------------------
// Copyright (C) 2001 Geoffrey Furnish
// Copyright (C) 2002 Alan W. Irwin
// Copyright (C) 2004 Andrew Ross
//
// This file is part of PLplot.
//
// PLplot is free software; you can redistribute it and/or modify
// it under the terms of the GNU Library General Public License as published by
// the Free Software Foundation; version 2 of the License.
//
// PLplot 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 Library General Public License for more details.
//
// You should have received a copy of the GNU Library General Public License
// along with PLplot; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
//--------------------------------------------------------------------------
//--------------------------------------------------------------------------
// Implementation of PLplot example 16 in Java.
//--------------------------------------------------------------------------
package plplot.examples;
import plplot.core.*;
import java.lang.Math;
class x16 {
// number of shade levels, x data points, y data points, and perimeter points.
static final int NSHADES = 20;
static final int XPTS = 35;
static final int YPTS = 46;
static final int PERIMETERPTS = 100;
// calculated constants and array that depends on them
static final double XSPA = 2. / ( XPTS - 1 );
static final double YSPA = 2. / ( YPTS - 1 );
final double tr[] = { XSPA, 0.0, -1.0, 0.0, YSPA, -1.0 };
PLStream pls = new PLStream();
double fmin, fmax;
// Compute min and max value of a 2-d array.
void f2mnmx( double[][] f, int nx, int ny )
{
fmax = f[0][0];
fmin = fmax;
for ( int i = 0; i < nx; i++ )
for ( int j = 0; j < ny; j++ )
{
if ( f[i][j] < fmin ) fmin = f[i][j];
if ( f[i][j] > fmax ) fmax = f[i][j];
}
}
// Does a variety of shade plots with continuous (cmap1) colours
public static void main( String[] args )
{
new x16( args );
}
public x16( String[] args )
{
int i, j;
double x, y, argx, argy, distort, r, t, zmin, zmax;
double[] px = new double[PERIMETERPTS];
double[] py = new double[PERIMETERPTS];
double[][] xg0 = new double[XPTS][YPTS];
double[][] yg0 = new double[XPTS][YPTS];
double[][] xg1 = new double[XPTS][YPTS];
double[][] yg1 = new double[XPTS][YPTS];
double[][] z = new double[XPTS][YPTS];
double[][] w = new double[XPTS][YPTS];
double[][] xg2 = new double[XPTS][YPTS];
double[][] yg2 = new double[XPTS][YPTS];
double[] clevel = new double[NSHADES];
double[] shedge = new double[NSHADES + 1];
final int fill_width = 2, cont_color = 0, cont_width = 0;
// Parse and process command line arguments.
pls.parseopts( args, PLStream.PL_PARSE_FULL | PLStream.PL_PARSE_NOPROGRAM );
// Load colour palettes
pls.spal0( "cmap0_black_on_white.pal" );
pls.spal1( "cmap1_gray.pal", true );
// Reduce colors in cmap 0 so that cmap 1 is useful on a
//16-color display
pls.scmap0n( 3 );
//Initialize plplot
pls.init();
// Set up data array
for ( i = 0; i < XPTS; i++ )
{
x = (double) ( i - ( XPTS / 2 ) ) / (double) ( XPTS / 2 );
for ( j = 0; j < YPTS; j++ )
{
y = (double) ( j - ( YPTS / 2 ) ) / (double) ( YPTS / 2 ) - 1.0;
z[i][j] = -Math.sin( 7. * x ) * Math.cos( 7. * y ) + x * x - y * y;
w[i][j] = -Math.cos( 7. * x ) * Math.sin( 7. * y ) + 2 * x * y;
}
}
f2mnmx( z, XPTS, YPTS );
zmin = fmin;
zmax = fmax;
for ( i = 0; i < NSHADES; i++ )
clevel[i] = zmin + ( zmax - zmin ) * ( i + 0.5 ) / (double) NSHADES;
for ( i = 0; i < NSHADES + 1; i++ )
shedge[i] = zmin + ( zmax - zmin ) * (double) i / (double) NSHADES;
for ( i = 0; i < XPTS; i++ )
{
for ( j = 0; j < YPTS; j++ )
{
// Replacement for mypltr of x16c.c
x = tr[0] * i + tr[1] * j + tr[2];
y = tr[3] * i + tr[4] * j + tr[5];
argx = x * Math.PI / 2;
argy = y * Math.PI / 2;
distort = 0.4;
// Note xg0 ==> yg1 are one-dimensional because of arrangement of
//zeros in the final tr definition above. However, for now
//we are using raw interface here so must nominally treat them
//as two-dimensional.
xg0[i][j] = x;
yg0[i][j] = y;
xg1[i][j] = x + distort * Math.cos( argx );
yg1[i][j] = y - distort * Math.cos( argy );
xg2[i][j] = x + distort * Math.cos( argx ) * Math.cos( argy );
yg2[i][j] = y - distort * Math.cos( argx ) * Math.cos( argy );
}
}
// Plot using identity transform
pls.adv( 0 );
pls.vpor( 0.1, 0.9, 0.1, 0.9 );
pls.wind( -1.0, 1.0, -1.0, 1.0 );
pls.psty( 0 );
pls.shades( z, -1., 1., -1., 1.,
shedge, fill_width,
cont_color, cont_width,
true, xg0, yg0 );
pls.col0( 1 );
pls.box( "bcnst", 0.0, 0, "bcnstv", 0.0, 0 );
pls.col0( 2 );
pls.lab( "distance", "altitude", "Bogon density" );
// Plot using 1d coordinate transform
// Load colour palettes
pls.spal0( "cmap0_black_on_white.pal" );
pls.spal1( "cmap1_blue_yellow.pal", true );
// Reduce colors in cmap 0 so that cmap 1 is useful on a
//16-color display
pls.scmap0n( 3 );
pls.adv( 0 );
pls.vpor( 0.1, 0.9, 0.1, 0.9 );
pls.wind( -1.0, 1.0, -1.0, 1.0 );
pls.psty( 0 );
pls.shades( z, -1., 1., -1., 1.,
shedge, fill_width,
cont_color, cont_width,
true, xg1, yg1 );
pls.col0( 1 );
pls.box( "bcnst", 0.0, 0, "bcnstv", 0.0, 0 );
pls.col0( 2 );
pls.lab( "distance", "altitude", "Bogon density" );
// Plot using 2d coordinate transform
// Load colour palettes
pls.spal0( "cmap0_black_on_white.pal" );
pls.spal1( "cmap1_blue_red.pal", true );
// Reduce colors in cmap 0 so that cmap 1 is useful on a
//16-color display
pls.scmap0n( 3 );
pls.adv( 0 );
pls.vpor( 0.1, 0.9, 0.1, 0.9 );
pls.wind( -1.0, 1.0, -1.0, 1.0 );
pls.psty( 0 );
pls.shades( z, -1., 1., -1., 1.,
shedge, fill_width,
cont_color, cont_width,
false, xg2, yg2 );
pls.col0( 1 );
pls.box( "bcnst", 0.0, 0, "bcnstv", 0.0, 0 );
pls.col0( 2 );
pls.cont( w, 1, XPTS, 1, YPTS, clevel, xg2, yg2 );
pls.lab( "distance", "altitude", "Bogon density, with streamlines" );
// Plot using 2d coordinate transform
// Load colour palettes
pls.spal0( "" );
pls.spal1( "", true );
// Reduce colors in cmap 0 so that cmap 1 is useful on a
//16-color display
pls.scmap0n( 3 );
pls.adv( 0 );
pls.vpor( 0.1, 0.9, 0.1, 0.9 );
pls.wind( -1.0, 1.0, -1.0, 1.0 );
pls.psty( 0 );
pls.shades( z, -1., 1., -1., 1.,
shedge, fill_width,
2, 3,
false, xg2, yg2 );
pls.col0( 1 );
pls.box( "bcnst", 0.0, 0, "bcnstv", 0.0, 0 );
pls.col0( 2 );
pls.lab( "distance", "altitude", "Bogon density" );
// Note this exclusion API will probably change so don't bother
// with it for x16.java example.
//Example with polar coordinates.
// Load colour palettes
pls.spal0( "cmap0_black_on_white.pal" );
pls.spal1( "cmap1_gray.pal", true );
// Reduce colors in cmap 0 so that cmap 1 is useful on a
//16-color display
pls.scmap0n( 3 );
pls.adv( 0 );
pls.vpor( .1, .9, .1, .9 );
pls.wind( -1., 1., -1., 1. );
pls.psty( 0 );
// Build new coordinate matrices.
for ( i = 0; i < XPTS; i++ )
{
r = ( (double) i ) / ( XPTS - 1 );
for ( j = 0; j < YPTS; j++ )
{
t = ( 2. * Math.PI / ( YPTS - 1. ) ) * j;
xg2[i][j] = r * Math.cos( t );
yg2[i][j] = r * Math.sin( t );
z[i][j] = Math.exp( -r * r ) * Math.cos( 5. * Math.PI * r ) * Math.cos( 5. * t );
}
}
//Need a new shedge to go along with the new data set.
f2mnmx( z, XPTS, YPTS );
zmin = fmin;
zmax = fmax;
for ( i = 0; i < NSHADES + 1; i++ )
shedge[i] = zmin + ( zmax - zmin ) * (double) i / (double) NSHADES;
pls.shades( z, -1., 1., -1., 1.,
shedge, fill_width,
cont_color, cont_width,
false, xg2, yg2 );
// Now we can draw the perimeter. (If do before, shade stuff may overlap.)
for ( i = 0; i < PERIMETERPTS; i++ )
{
t = ( 2. * Math.PI / ( PERIMETERPTS - 1 ) ) * (double) i;
px[i] = Math.cos( t );
py[i] = Math.sin( t );
}
pls.col0( 1 );
pls.line( px, py );
// And label the plot.
pls.col0( 2 );
pls.lab( "", "", "Tokamak Bogon Instability" );
// Clean up
pls.end();
}
}
//--------------------------------------------------------------------------
// End of x16.java
//--------------------------------------------------------------------------
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