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Asymptote (Vector Graphics Language)

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Intersection points

pair[] intersectionpoints(path, path);

Examples:

size(8cm,0);
import math;
import graph;
real r,s;
pair a,b, common;
path circ1, circ2;
r=1; s=1;
a=(0,0);
b=(1,0);
circ1=circle(a,r);
circ2=circle(b,s);
draw(circ1,linewidth(1bp));
draw(circ2,1bp+green);
pair [] x=intersectionpoints(circ1, circ2);
dot(x[0],3bp+blue);
dot(x[1],3bp+blue);
draw(x[0] -- x[1],1bp+red);

path g=(-3,-sqrt(3))--(3,-sqrt(3))--(0,2*sqrt(3))--cycle;
draw(g,black);
path p=-2/3*(-3,-sqrt(3))--(-2/3)*(3,-sqrt(3))--(-2/3)*(0,2*sqrt(3))--cycle;
draw(p,black);
pair [] x=intersectionpoints(g, p);
fill(x[0]--x[1]--x[2]--x[3]--x[4]--x[5]--cycle,black);
dot((0,0),white);

Note that this function will cause an error if the paths involved do not intersect.

Next: CSE5