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log2
Langue: en
Version: 2007-07-26 (mandriva - 22/10/07)
Section: 3 (Bibliothèques de fonctions)
NAME
log2, log2f, log2l - base-2 logarithmic functionSYNOPSIS
#include <math.h> 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 requirements.SEE ALSO
cbrt(3), clog2(3), sqrt(3)Contenus ©2006-2024 Benjamin Poulain
Design ©2006-2024 Maxime Vantorre