NAME

log, logf, logl - natural logarithmic function

SYNOPSIS

#include <math.h>

double log(double x);

float logf(float x);

long double logl(long double x);

Link with -lm.

DESCRIPTION

The log() function returns the natural logarithm of x.

ERRORS

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), clog(3), log1p(3), sqrt(3)

COLOPHON

This page is part of release 3.05 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/.