Other Alias
fabs, fabslSYNOPSIS
#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.
COLOPHON
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