ref: ac7d3b519a8c87d17fc16fd269cba1b4729d9a15
dir: /sys/src/cmd/map/libmap/ccubrt.c/
#include <u.h> #include <libc.h> #include "map.h" void ccubrt(double zr, double zi, double *wr, double *wi) { double r, theta; theta = atan2(zi,zr); r = cubrt(hypot(zr,zi)); *wr = r*cos(theta/3); *wi = r*sin(theta/3); }