abs

Compute the absolute value for each element in an ndarray.

Installation

npm install @stdlib/math-special-abs

Usage

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

abs( x[, options] )

Computes the absolute value for each element in an ndarray.

var ndarray2array = require( '@stdlib/ndarray-to-array' );
var array = require( '@stdlib/ndarray-array' );

var x = array( [ [ -1.0, -2.0 ], [ -3.0, -4.0 ] ] );
var y = abs( x );
// returns <ndarray>

var arr = ndarray2array( y );
// returns [ [ 1.0, 2.0 ], [ 3.0, 4.0 ] ]

The function accepts the following arguments:

• x: input ndarray.
• options: function options (optional).

The function accepts the following options:

• dtype: output ndarray data type. Must be a real-valued or generic data type.
• order: output ndarray order (i.e., memory layout).

By default, the function returns an ndarray having a data type determined by the function's output data type policy. To override the default behavior, set the dtype option.

var ndarray2array = require( '@stdlib/ndarray-to-array' );
var array = require( '@stdlib/ndarray-array' );
var getDType = require( '@stdlib/ndarray-dtype' );

var x = array( [ [ -1.0, -2.0 ], [ -3.0, -4.0 ] ] );
var y = abs( x, {
    'dtype': 'generic'
});
// returns <ndarray>

var dt = getDType( y );
// returns 'generic'

var arr = ndarray2array( y );
// returns [ [ 1.0, 2.0 ], [ 3.0, 4.0 ] ]

By default, the function returns an ndarray having the same order as the input ndarray. To return an ndarray having a specific memory layout irrespective of the memory layout of the input ndarray, set the order option.

var ndarray2array = require( '@stdlib/ndarray-to-array' );
var array = require( '@stdlib/ndarray-array' );
var getOrder = require( '@stdlib/ndarray-order' );

var x = array( [ [ -1.0, -2.0 ], [ -3.0, -4.0 ] ] );
var y = abs( x, {
    'order': 'column-major'
});
// returns <ndarray>

var ord = getOrder( y );
// returns 'column-major'

var arr = ndarray2array( y );
// returns [ [ 1.0, 2.0 ], [ 3.0, 4.0 ] ]

abs.assign( x, y )

Computes the absolute value for each element in an ndarray and assigns results to a provided output ndarray.

var ndarray2array = require( '@stdlib/ndarray-to-array' );
var array = require( '@stdlib/ndarray-array' );

var x = array( [ [ -1.0, -2.0 ], [ -3.0, -4.0 ] ] );
var y = array( [ [ 0.0, 0.0 ], [ 0.0, 0.0 ] ] );

var out = abs.assign( x, y );
// returns <ndarray>

var bool = ( out === y );
// returns true

var arr = ndarray2array( out );
// returns [ [ 1.0, 2.0 ], [ 3.0, 4.0 ] ]

The function accepts the following arguments:

• x: input ndarray. Must have a shape which is broadcast-compatible with the shape of the output ndarray.
• y: output ndarray.

The function supports broadcasting an input ndarray to the shape of the output ndarray without performing a physical copy of the input ndarray's underlying data.

var ndarray2array = require( '@stdlib/ndarray-to-array' );
var zeros = require( '@stdlib/ndarray-zeros' );
var array = require( '@stdlib/ndarray-array' );

// Create a 2x2 input ndarray:
var x = array( [ [ -1.0, -2.0 ], [ -3.0, -4.0 ] ] );

// Create a 2x2x2 output ndarray:
var y = zeros( [ 2, 2, 2 ] );

var out = abs.assign( x, y );
// returns <ndarray>

var arr = ndarray2array( out );
// returns [ [ [ 1.0, 2.0 ], [ 3.0, 4.0 ] ], [ [ 1.0, 2.0 ], [ 3.0, 4.0 ] ] ]

Notes

• The output data type policy only applies to the main function and specifies that, by default, the function must return an ndarray having a real-valued or "generic" data type. For the assign method, the output ndarray is allowed to have any supported output data type.

Examples

var uniform = require( '@stdlib/random-uniform' );
var ndarray2array = require( '@stdlib/ndarray-to-array' );
var abs = require( '@stdlib/math-special-abs' );

var x = uniform( [ 5, 5 ], -10.0, 10.0 );
console.log( ndarray2array( x ) );

var y = abs( x );
console.log( ndarray2array( y ) );

Notice

This package is part of stdlib, a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.

For more information on the project, filing bug reports and feature requests, and guidance on how to develop stdlib, see the main project repository.

Community

License

See LICENSE.

Copyright

Copyright © 2016-2026. The Stdlib Authors.