log2(3)                    Library Functions Manual                    log2(3)

NAME
       log2, log2f, log2l - base-2 logarithmic function

LIBRARY
       Math library (libm, -lm)

SYNOPSIS
       #include <math.h>

       double log2(double x);
       float log2f(float x);
       long double log2l(long double x);

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

       log2(), log2f(), log2l():
           _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L

DESCRIPTION
       These functions return the base-2 logarithm of x.

RETURN VALUE
       On success, these functions return the base-2 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).

       +--------------------------------------------+---------------+---------+
       |Interface                                   | Attribute     | Value   |
       +--------------------------------------------+---------------+---------+
       |log2 (), log2f (), log2l ()                 | Thread safety | MT-Safe |
       +--------------------------------------------+---------------+---------+
STANDARDS
       C11, POSIX.1-2008.

HISTORY
       glibc 2.1.  C99, POSIX.1-2001.

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

SEE ALSO
       cbrt(3), clog2(3), log(3), log10(3), sqrt(3)

Linux man-pages 6.7               2024-03-12                           log2(3)