FABS(3)                             Linux Programmer's Manual                             FABS(3)



NAME
       fabs, fabsf, fabsl - absolute value of floating-point number

SYNOPSIS
       #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
   Multithreading (see pthreads(7))
       The fabs(), fabsf(), and fabsl() functions are thread-safe.

CONFORMING TO
       C99, POSIX.1-2001.  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
       This page is part of release 3.74 of the Linux man-pages project.  A  description  of  the
       project,  information  about  reporting  bugs, and the latest version of this page, can be
       found at http://www.kernel.org/doc/man-pages/.



                                            2013-07-10                                    FABS(3)