shithub: npe

ref: ab3b4d3d9fc91716220b146dc0f57653a5b1daf4
dir: /libnpe/log2.c/

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#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);
}