npm package: @stdlib/array-base-insert-at
Description: Insert an element into an array.
Author: The Stdlib Authors
Latest version: 0.1.1

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    About stdlib...
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# insertAt

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

> Insert an element into an 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-base-insert-at
```

</section>

<section class="usage">

## Usage

```javascript
var insertAt = require( '@stdlib/array-base-insert-at' );
```

#### insertAt( x, index, value )

Inserts an element into an array.

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

var y = insertAt( x, -3, 4 );
// returns [ 1, 1, 4, 2, 3, 3 ]

var bool = ( x === y );
// returns true
```

The function accepts the following arguments:

-   **x**: an input array.
-   **index**: element index.
-   **value**: value to insert.

</section>

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

<section class="notes">

## Notes

-   Negative indices are resolved relative to the last array element, with the last element corresponding to `-1`.
-   If provided an out-of-bounds index, the function clamps the index to the beginning or end of the array.
-   The function mutates the input array.

</section>

<!-- /.notes -->

<!-- Package usage examples. -->

<section class="examples">

## Examples

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

```javascript
var discreteUniform = require( '@stdlib/random-array-discrete-uniform' );
var randi = require( '@stdlib/random-base-discrete-uniform' );
var insertAt = require( '@stdlib/array-base-insert-at' );

// Create an array of random numbers:
var x = discreteUniform( 10, 0, 5, {
    'dtype': 'generic'
});
// returns [...]

console.log( x );

// Insert a random element:
var y = insertAt( x, randi( 0, x.length ), randi( 100, 105 ) );
// returns [...]

console.log( y );
```

</section>

<!-- /.examples -->

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* * *

## 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].

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

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

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