fabs, fabsf, fabsl - absolute value of floating-point number
#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)):
These functions return the absolute value of the floating-point number x
.
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.
No errors occur.
For an explanation of the terms used in this section, see attributes(7).
Interface | Attribute | Value |
fabs(), fabsf(), fabsl() | Thread safety | MT-Safe |
C99, POSIX.1-2001, POSIX.1-2008.
The variant returning double
also conforms to SVr4, 4.3BSD, C89.
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