fabs(3) - BetterMan

fabs(3)

absolute value of floating-point number

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Synopsis

#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

—

NAME

fabs, fabsf, fabsl - absolute value of floating-point number

LIBRARY

Math library (libm, -lm)

SYNOPSIS

bash

#include <math.h>

bash

double fabs(double \nx\n);\n
\nfloat fabsf(float \nx\n);\n
\nlong double fabsl(long double \nx\n);

fabsf(), fabsl():

bash


\n
    _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
\n
        || /* Since glibc 2.19: */ _DEFAULT_SOURCE
\n
        || /* 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.