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():
           _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
               || /* Since glibc 2.19: */ _DEFAULT_SOURCE
               || /* Glibc versions <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE

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).

       allbox; lbw24 lb  lb  l  l  l.   Interface Attribute Value  T{  fabs(),
       fabsf(), fabsl() T}   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
       This  page  is  part of release 4.16 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
       https://www.kernel.org/doc/man-pages/.



                                  2017-09-15                           FABS(3)