LOG2(3) Linux Programmers Manual LOG2(3)
NAME
log2, log2f, log2l  base2 logarithmic function
SYNOPSIS
#include
double log2(double x);
float log2f(float x);
long double log2l(long double x);
Link with lm.
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
log2(), log2f(), log2l(): _XOPEN_SOURCE >= 600  _ISOC99_SOURCE; or
cc std=c99
DESCRIPTION
The log2() function returns the base 2 logarithm of x.
ERRORS
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).
CONFORMING TO
SVr4, 4.3BSD, C89. The float and long double variants are C99 require
ments.
SEE ALSO
cbrt(3), clog2(3), sqrt(3)
COLOPHON
This page is part of release 3.05 of the Linux manpages project. A
description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/manpages/.
20070726 LOG2(3)
