ref: dd1055daf99d53d1d16ed1ae37a7dd24e68f1f93
dir: /libnpe/log2.c/
#include <math.h> #include "_npe.h" double log2(double x) { if(x == 0) return -hugeD; if(x < 0 || isNaN(x)) return NaN(); return log(x)*ln2o1; } float log2f(float x) { if(x == 0) return -hugeF; return log2(x); }