log10

NAME

log10, log10f, log10l - base-10 logarithmic function

LIBRARY

Math library (libm, -lm)

SYNOPSIS

#include <math.h>

double log10(double x);
float log10f(float x);
long double log10l(long double x);

Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

log10f(), log10l():
_ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
|| /* Since glibc 2.19: */ _DEFAULT_SOURCE
|| /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE

DESCRIPTION

These functions return the base 10 logarithm of x.

RETURN VALUE

On success, these functions return the base 10 logarithm of x.

For special cases, including where x is 0, 1, negative, infinity, or NaN, see log(3).

ERRORS

See math_error(7) for information on how to determine whether an error has occurred when calling these functions.

For a discussion of the errors that can occur for these functions, see log(3).

ATTRIBUTES

For an explanation of the terms used in this section, see attributes(7).

STANDARDS

C99, POSIX.1-2001, POSIX.1-2008.

The variant returning double also conforms to SVr4, 4.3BSD.

SEE ALSO

cbrt(3), clog10(3), exp10(3), log(3), log2(3), sqrt(3)