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// Plot a 3D function
import java.lang.Math;
public class runme {
static {
try {
System.loadLibrary("gifplot");
} catch (UnsatisfiedLinkError e) {
System.err.println("Native code library failed to load. See the chapter on Dynamic Linking Problems in the SWIG Java documentation for help.\n" + e);
System.exit(1);
}
}
public static void main(String argv[]) {
// Here are some plotting parameters
double xmin = -5.0;
double xmax = 5.0;
double ymin = -5.0;
double ymax = 5.0;
double zmin = -5.0;
double zmax = 5.0;
// Grid resolution
int nxpoints = 60;
int nypoints = 60;
ColorMap cmap = new ColorMap("cmap");
FrameBuffer frame = new FrameBuffer(500,500);
frame.clear((short)gifplot.BLACK);
Plot3D p3 = new Plot3D(frame,xmin,ymin,zmin,xmax,ymax,zmax);
p3.lookat(2*(zmax-zmin));
p3.autoperspective(40);
p3.rotu(60);
p3.rotr(30);
p3.rotd(10);
System.out.println( "Making a nice 3D plot..." );
p3.clear((short)gifplot.BLACK);
p3.start();
double dx = 1.0*(xmax-xmin)/nxpoints;
double dy = 1.0*(ymax-ymin)/nypoints;
double cscale = 240.0/(zmax-zmin);
double x = xmin;
for (int i = 0; i < nxpoints; i++) {
double y = ymin;
for (int j = 0; j < nypoints; j++) {
double z1 = func(x,y);
double z2 = func(x+dx,y);
double z3 = func(x+dx,y+dy);
double z4 = func(x,y+dy);
double c1 = cscale*(z1-zmin);
double c2 = cscale*(z2-zmin);
double c3 = cscale*(z3-zmin);
double c4 = cscale*(z4-zmin);
double c = (c1+c2+c3+c4)/4;
if (c < 0) c = 0;
if (c > 239) c = 239;
p3.solidquad(x,y,z1,x+dx,y,z2,x+dx,y+dy,z3,x,y+dy,z4,(short)(c+16));
y = y + dy;
}
x = x + dx;
}
frame.writeGIF(cmap,"image.gif");
System.out.println( "Wrote image.gif" );
}
// Here is the function to plot
public static double func(double x, double y) {
return 5*java.lang.Math.cos(2*java.lang.Math.sqrt(x*x+y*y))*java.lang.Math.exp(-0.3*java.lang.Math.sqrt(x*x+y*y));
}
}
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