Absolute Value

Compute an absolute value.

The absolute value is defined as

Usage

var abs = require( '@stdlib/math/base/special/fast/abs' );

abs( x )

Computes an absolute value.

var v = abs( -1.0 );
// returns 1.0

v = abs( 2.0 );
// returns 2.0

v = abs( 0.0 );
// returns 0.0

v = abs( NaN );
// returns NaN

Notes

This implementation is not IEEE 754 compliant. If provided -0, the function returns -0.
```
var v = abs( -0.0 );
// returns -0.0
```

Examples

var randu = require( '@stdlib/random/base/randu' );
var round = require( '@stdlib/math/base/special/round' );
var abs = require( '@stdlib/math/base/special/fast/abs' );

var rand;
var i;

for ( i = 0; i < 100; i++ ) {
    rand = round( randu() * 100.0 ) - 50.0;
    console.log( 'abs(%d) = %d', rand, abs( rand ) );
}

C APIs

Usage

#include "stdlib/math/base/special/fast/abs.h"

stdlib_base_fast_abs( x )

Computes the absolute value of a double-precision floating-point number.

double y = stdlib_base_fats_abs( -5.0 );
// returns 5.0

The function accepts the following arguments:

x: [in] double input value.

double stdlib_base_fast_abs( const double x );

Examples

#include "stdlib/math/base/special/fast/abs.h"
#include <stdio.h>

int main( void ) {
    const double x[] = { 3.14, -3.14, 0.0, 0.0/0.0 };

    double y;
    int i;
    for ( i = 0; i < 4; i++ ) {
        y = stdlib_base_fast_abs( x[ i ] );
        printf( "|%lf| = %lf\n", x[ i ], y );
    }
}