CentOS 5.6

GNU/Linux	CentOS 5.6
	log2l(3)

LOG2

NAME

log2, log2f, log2l − base-2 logarithmic function

#include <math.h>

double log2(double x);
float log2f(float x);
long double log2l(long double x);

Compile with −std=c99; link with −lm.

The log2() function returns the base 2 logarithm of x.

The log2() function can return the following error:

	EDOM		The argument x is negative.
	ERANGE		The argument x is zero. The log of zero is not defined (minus infinity).

SVr4, 4.3BSD, C89. The float and long double variants are C99 requirements.