fabsf

       #include <math.h>

       double fabs(double x);
       float fabsf(float x);
       long double fabsl(long double x);

       Link with -lm.

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

       fabsf(), fabsl():
           _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 600 ||
           _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L;
           or cc -std=c99

DESCRIPTION
       These functions return the absolute value of the floating-point  number
       x.

RETURN VALUE
       These functions return the absolute value of x.

       If x is a NaN, a NaN is returned.

       If x is -0, +0 is returned.

       If  x  is  negative infinity or positive infinity, positive infinity is
       returned.

ERRORS
       No errors occur.

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

       +-------------------------+---------------+---------+
       |Interface                | Attribute     | Value   |
       +-------------------------+---------------+---------+
       |fabs(), fabsf(), fabsl() | Thread safety | MT-Safe |
       +-------------------------+---------------+---------+
CONFORMING TO
       C99, POSIX.1-2001, POSIX.1-2008.

       The variant returning double also conforms to SVr4, 4.3BSD, C89.

SEE ALSO
       abs(3), cabs(3), ceil(3), floor(3), labs(3), rint(3)

COLOPHON
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