fabs - Man Page

Math library (libm, -lm)

#include <math.h>

double fabs(double x);
float fabsf(float x);
long double fabsl(long double x);

fabsf(), fabsl():

    _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
        || /* Since glibc 2.19: */ _DEFAULT_SOURCE
        || /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE

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).

C11, POSIX.1-2008.

C99, POSIX.1-2001.

The variant returning double also conforms to SVr4, 4.3BSD, C89.

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

abs(3), unu-1op(1).

The man pages fabsf(3) and fabsl(3) are aliases of fabs(3).