FABS
Section: Linux Programmer's Manual (3)
Updated: 2017-09-15
Page Index
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).
| 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
This page is part of release 5.10 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/.