npm package: @stdlib/array-empty-like
Description: Create an uninitialized array having the same length and data type as a provided array.
Author: The Stdlib Authors
Latest version: 0.3.1

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<details>
  <summary>
    About stdlib...
  </summary>
  <p>We believe in a future in which the web is a preferred environment for numerical computation. To help realize this future, we've built stdlib. stdlib is a standard library, with an emphasis on numerical and scientific computation, written in JavaScript (and C) for execution in browsers and in Node.js.</p>
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</details>

# emptyLike

[![NPM version][npm-image]][npm-url] [![Build Status][test-image]][test-url] [![Coverage Status][coverage-image]][coverage-url] <!-- [![dependencies][dependencies-image]][dependencies-url] -->

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

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<section class="intro">

</section>

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<!-- Package usage documentation. -->

<section class="installation">

## Installation

```bash
npm install @stdlib/array-empty-like
```

</section>

<section class="usage">

## Usage

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

#### emptyLike( x\[, dtype] )

Creates an uninitialized array having the same length and [data type][@stdlib/array/dtypes] as a provided array `x`.

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

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

By default, the output array [data type][@stdlib/array/dtypes] is inferred from the provided array `x`. To return an array having a different [data type][@stdlib/array/dtypes], provide a `dtype` argument.

```javascript
var x = [ 1, 1 ];

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

</section>

<!-- /.usage -->

<!-- Package usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->

<section class="notes">

## 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.

</section>

<!-- /.notes -->

<!-- Package usage examples. -->

<section class="examples">

## Examples

<!-- eslint no-undef: "error" -->

```javascript
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 );
}
```

</section>

<!-- /.examples -->

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<section class="references">

</section>

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<!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. -->

<section class="related">

* * *

## See Also

-   <span class="package-name">[`@stdlib/array-empty`][@stdlib/array/empty]</span><span class="delimiter">: </span><span class="description">create an uninitialized array having a specified length.</span>
-   <span class="package-name">[`@stdlib/array-full-like`][@stdlib/array/full-like]</span><span class="delimiter">: </span><span class="description">create a filled array having the same length and data type as a provided array.</span>
-   <span class="package-name">[`@stdlib/array-ones-like`][@stdlib/array/ones-like]</span><span class="delimiter">: </span><span class="description">create an array filled with ones and having the same length and data type as a provided array.</span>
-   <span class="package-name">[`@stdlib/array-zeros-like`][@stdlib/array/zeros-like]</span><span class="delimiter">: </span><span class="description">create a zero-filled array having the same length and data type as a provided array.</span>
-   <span class="package-name">[`@stdlib/ndarray-empty-like`][@stdlib/ndarray/empty-like]</span><span class="delimiter">: </span><span class="description">create an uninitialized ndarray having the same shape and data type as a provided ndarray.</span>

</section>

<!-- /.related -->

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<section class="main-repo" >

* * *

## Notice

This package is part of [stdlib][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][stdlib], see the main project [repository][stdlib].

#### Community

[![Chat][chat-image]][chat-url]

---

## License

See [LICENSE][stdlib-license].


## Copyright

Copyright &copy; 2016-2026. The Stdlib [Authors][stdlib-authors].

</section>

<!-- /.stdlib -->

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[npm-image]: http://img.shields.io/npm/v/@stdlib/array-empty-like.svg
[npm-url]: https://npmjs.org/package/@stdlib/array-empty-like

[test-image]: https://github.com/stdlib-js/array-empty-like/actions/workflows/test.yml/badge.svg?branch=v0.3.1
[test-url]: https://github.com/stdlib-js/array-empty-like/actions/workflows/test.yml?query=branch:v0.3.1

[coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/array-empty-like/main.svg
[coverage-url]: https://codecov.io/github/stdlib-js/array-empty-like?branch=main

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[stdlib]: https://github.com/stdlib-js/stdlib

[stdlib-authors]: https://github.com/stdlib-js/stdlib/graphs/contributors

[umd]: https://github.com/umdjs/umd
[es-module]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Modules

[deno-url]: https://github.com/stdlib-js/array-empty-like/tree/deno
[deno-readme]: https://github.com/stdlib-js/array-empty-like/blob/deno/README.md
[umd-url]: https://github.com/stdlib-js/array-empty-like/tree/umd
[umd-readme]: https://github.com/stdlib-js/array-empty-like/blob/umd/README.md
[esm-url]: https://github.com/stdlib-js/array-empty-like/tree/esm
[esm-readme]: https://github.com/stdlib-js/array-empty-like/blob/esm/README.md
[branches-url]: https://github.com/stdlib-js/array-empty-like/blob/main/branches.md

[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/array-empty-like/main/LICENSE

[@stdlib/array/dtypes]: https://www.npmjs.com/package/@stdlib/array-dtypes

<!-- <related-links> -->

[@stdlib/array/empty]: https://www.npmjs.com/package/@stdlib/array-empty

[@stdlib/array/full-like]: https://www.npmjs.com/package/@stdlib/array-full-like

[@stdlib/array/ones-like]: https://www.npmjs.com/package/@stdlib/array-ones-like

[@stdlib/array/zeros-like]: https://www.npmjs.com/package/@stdlib/array-zeros-like

[@stdlib/ndarray/empty-like]: https://www.npmjs.com/package/@stdlib/ndarray-empty-like

<!-- </related-links> -->

</section>

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