fabs(3) | Library Functions Manual | fabs(3) |
NAME
fabs, fabsf, fabsl - absolute value of floating-point number
LIBRARY
Math library (libm, -lm)
SYNOPSIS
#include <math.h>
double fabs(double x); float fabsf(float x); long double fabsl(long double x);
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 <= 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 |
STANDARDS
C11, POSIX.1-2008.
HISTORY
C99, POSIX.1-2001.
The variant returning double also conforms to SVr4, 4.3BSD, C89.
SEE ALSO
2024-05-02 | Linux man-pages 6.9.1 |