ref: 43a3a80be3cd9fe7e0f31efe5c24c3e321e07b08 dir: /sys/src/ape/lib/ap/math/fmin.c/
#include <math.h> double fmin(double a, double b) { if(isNaN(a)) return b; if(isNaN(b)) return a; return a < b ? a : b; }