npm package: @stdlib/array-base-take2d
Description: Take elements from a two-dimensional nested array.
Author: The Stdlib Authors
Latest version: 0.2.3

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# take2d

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

> Take elements from a two-dimensional nested array.

<section class="installation">

## Installation

```bash
npm install @stdlib/array-base-take2d
```

</section>

<section class="usage">

## Usage

```javascript
var take2d = require( '@stdlib/array-base-take2d' );
```

#### take2d( x, indices, dimension, mode )

Takes elements along a specified `dimension` from a two-dimensional nested array according to a specified [index `mode`][@stdlib/ndarray/index-modes].

```javascript
var x = [ [ 1, 2 ], [ 3, 4 ] ];
var indices = [ 1, 1, 0, 0, -1, -1 ];

var y = take2d( x, indices, 1, 'normalize' );
// returns [ [ 2, 2, 1, 1, 2, 2 ], [ 4, 4, 3, 3, 4, 4 ] ]
```

The function accepts the following arguments:

-   **x**: input nested array.
-   **indices**: list of indices.
-   **dimension**: dimension along which to take elements. If provided a negative integer, the dimension is resolved relative to the last dimension, with the last dimension being `-1`.
-   **mode**: [index mode][@stdlib/ndarray/index-modes] specifying how to handle an index which is out-of-bounds.

If `indices` is an empty array, the function returns empty arrays along the specified `dimension`.

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

var y = take2d( x, [], 1, 'throw' );
// returns [ [], [] ]

var z = take2d( x, [], 0, 'throw' );
// returns []
```

</section>

<!-- /.usage -->

<section class="notes">

## Notes

-   The function does **not** deep copy nested array elements.

</section>

<!-- /.notes -->

<section class="examples">

## Examples

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

```javascript
var filled2dBy = require( '@stdlib/array-base-filled2d-by' );
var filledBy = require( '@stdlib/array-base-filled-by' );
var discreteUniform = require( '@stdlib/random-base-discrete-uniform' );
var take2d = require( '@stdlib/array-base-take2d' );

// Generate a random array:
var shape = [ 5, 5 ];
var x = filled2dBy( shape, discreteUniform.factory( 0, 100 ) );
console.log( x );

// Generate an array of random indices:
var N = discreteUniform( 5, 15 );
var indices = filledBy( N, discreteUniform.factory( 0, shape[1]-1 ) );
console.log( indices );

// Take a random sample of elements from `x`:
var y = take2d( x, indices, 1, 'throw' );
console.log( y );
```

</section>

<!-- /.examples -->

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

<section class="related">

</section>

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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-url]: https://npmjs.org/package/@stdlib/array-base-take2d

[test-image]: https://github.com/stdlib-js/array-base-take2d/actions/workflows/test.yml/badge.svg?branch=v0.2.3
[test-url]: https://github.com/stdlib-js/array-base-take2d/actions/workflows/test.yml?query=branch:v0.2.3

[coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/array-base-take2d/main.svg
[coverage-url]: https://codecov.io/github/stdlib-js/array-base-take2d?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-base-take2d/tree/deno
[deno-readme]: https://github.com/stdlib-js/array-base-take2d/blob/deno/README.md
[umd-url]: https://github.com/stdlib-js/array-base-take2d/tree/umd
[umd-readme]: https://github.com/stdlib-js/array-base-take2d/blob/umd/README.md
[esm-url]: https://github.com/stdlib-js/array-base-take2d/tree/esm
[esm-readme]: https://github.com/stdlib-js/array-base-take2d/blob/esm/README.md
[branches-url]: https://github.com/stdlib-js/array-base-take2d/blob/main/branches.md

[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/array-base-take2d/main/LICENSE

[@stdlib/ndarray/index-modes]: https://www.npmjs.com/package/@stdlib/ndarray-index-modes

</section>

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