Chapter 8: Base modules
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real f(real x, real y) {return x^2-y^2;} int n=10; real[] c=new real[n]; for(int i=0; i < n; ++i) c[i]=(i-n/2)/n; pen[] p=sequence(new pen(int i) { return (c[i] >= 0 ? solid : dashed)+fontsize(6pt); },c.length); Label[] Labels=sequence(new Label(int i) { return Label(c[i] != 0 ? (string) c[i] : UnFill(1bp)); },c.length);
"",Relative(unitrand()),(0,0),
draw(Labels,contour(f,(-1,-1),(1,1),c),p); -0.5
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The next example illustrates how contour lines can be drawn on color density images: import graph; import palette; import contour; size(10cm,10cm,IgnoreAspect); pair a=(0,0); pair b=(2pi,2pi); real f(real x, real y) {return cos(x)*sin(y);} int N=200; int Divs=10; int divs=2;