fabs

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).

STANDARDS

C99, POSIX.1-2001, POSIX.1-2008.

The variant returning double also conforms to SVr4, 4.3BSD.

SEE ALSO

abs(3), cabs(3), ceil(3), floor(3), labs(3), rint(3)