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emptyLike

Create an uninitialized array having the same length and data type as a provided array.

Installation

npm install @stdlib/array-empty-like

Alternatively,

• To load the package in a website via a script tag without installation and bundlers, use the ES Module available on the esm branch (see README).
• If you are using Deno, visit the deno branch (see README for usage intructions).
• For use in Observable, or in browser/node environments, use the Universal Module Definition (UMD) build available on the umd branch (see README).

The branches.md file summarizes the available branches and displays a diagram illustrating their relationships.

To view installation and usage instructions specific to each branch build, be sure to explicitly navigate to the respective README files on each branch, as linked to above.

Usage

var emptyLike = require( '@stdlib/array-empty-like' );

emptyLike( x[, dtype] )

Creates an uninitialized array having the same length and data type as a provided array x.

var x = [ 1, 2, 3, 4, 5 ];

var arr = emptyLike( x );
// returns [ 0, 0, 0, 0, 0 ];

By default, the output array data type is inferred from the provided array x. To return an array having a different data type, provide a dtype argument.

var x = [ 1, 1 ];

var arr = emptyLike( x, 'int32' );
// returns <Int32Array>

Notes

• In browser environments, the function always returns zero-filled arrays.
• If dtype is 'generic', the function always returns a zero-filled array.
• In Node.js versions >=3.0.0, the underlying memory of returned typed arrays is not initialized. Memory contents are unknown and may contain sensitive data.

Examples

var dtypes = require( '@stdlib/array-dtypes' );
var zeros = require( '@stdlib/array-zeros' );
var emptyLike = require( '@stdlib/array-empty-like' );

// Create a zero-filled array:
var x = zeros( 4, 'complex128' );

// Get a list of array data types:
var dt = dtypes();

// Generate empty arrays...
var arr;
var i;
for ( i = 0; i < dt.length; i++ ) {
    arr = emptyLike( x, dt[ i ] );
    console.log( arr );
}

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See Also

• @stdlib/array-empty: create an uninitialized array having a specified length.
• @stdlib/array-full-like: create a filled array having the same length and data type as a provided array.
• @stdlib/array-ones-like: create an array filled with ones and having the same length and data type as a provided array.
• @stdlib/array-zeros-like: create a zero-filled array having the same length and data type as a provided array.
• @stdlib/ndarray-empty-like: create an uninitialized ndarray having the same shape and data type as a provided ndarray.

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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

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License

See LICENSE.

Copyright

Copyright © 2016-2024. The Stdlib Authors.