Meg's Mirrors

zig

1	#include <math.h>
2
3	/*
4	special cases:
5	logb(+-0) = -inf, and raise divbyzero
6	logb(+-inf) = +inf
7	logb(nan) = nan
8	*/
9
10	double logb(double x)
11	{
12	if (!isfinite(x))
13	return x * x;
14	if (x == 0)
15	return -1/(x*x);
16	return ilogb(x);
17	}