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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).

VERSIONS
       These functions were added in glibc 2.1.

ATTRIBUTES
       For an  explanation  of  the  terms  used  in  this  section,  see  at-
       tributes(7).

       ┌────────────────────────────────────────────┬───────────────┬─────────┐
       │InterfaceAttributeValue   │
       ├────────────────────────────────────────────┼───────────────┼─────────┤
       │log2(), log2f(), log2l()                    │ Thread safety │ MT-Safe │
       └────────────────────────────────────────────┴───────────────┴─────────┘

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

       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 6.03              2022-12-15                           log2(3)

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