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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)