NAME |LIBRARY |SYNOPSIS |DESCRIPTION |RETURN VALUE |ERRORS |ATTRIBUTES |STANDARDS |HISTORY |SEE ALSO |COLOPHON | |
log10(3) Library Functions Manuallog10(3)log10, log10f, log10l - base-10 logarithmic function
Math library (libm,-lm)
#include <math.h>double log10(doublex);float log10f(floatx);long double log10l(long doublex); Feature Test Macro Requirements for glibc (seefeature_test_macros(7)):log10f(),log10l(): _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L || /* Since glibc 2.19: */ _DEFAULT_SOURCE || /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
These functions return the base-10 logarithm ofx.
On success, these functions return the base-10 logarithm ofx. For special cases, including wherex is 0, 1, negative, infinity, or NaN, seelog(3).
Seemath_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, seelog(3).
For an explanation of the terms used in this section, seeattributes(7). ┌──────────────────────────────────────┬───────────────┬─────────┐ │Interface│Attribute│Value│ ├──────────────────────────────────────┼───────────────┼─────────┤ │log10(),log10f(),log10l() │ Thread safety │ MT-Safe │ └──────────────────────────────────────┴───────────────┴─────────┘
C11, POSIX.1-2008.
C99, POSIX.1-2001. The variant returningdouble also conforms to SVr4, 4.3BSD, C89.
cbrt(3),clog10(3),exp10(3),log(3),log2(3),sqrt(3)
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