import base_pi;
size(8cm,0);

path cle=yscale(3)*((0,0){N}..(1,0){N}..cycle);
draw(cle);

real y=0.1;
/*<asyxml><view file="../base_pi.asy" type="real[]" signature="intersectsh(path,real)"/></asyxml>*/
real[] it=intersectsh(cle,y);
draw(subpath(cle,it[0],it[1]), 1mm+blue);
draw(subpath(cle,it[1],it[2]), 1mm+.8green);
dot(intersectionpointsh(cle,y),red);
drawline((0,y),(1,y));