npm package: @stdlib/array-base-to-inserted-at
Description: Return a new array containing every element from an input array and with a provided value inserted at a specified index.
Author: The Stdlib Authors
Latest version: 0.1.1

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# toInsertedAt

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

> Return a new array containing every element from an input array and with a provided value inserted at a specified index.

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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-to-inserted-at
```

</section>

<section class="usage">

## Usage

```javascript
var toInsertedAt = require( '@stdlib/array-base-to-inserted-at' );
```

#### toInsertedAt( x, index, value )

Returns a new array containing every element from an input array and with a provided value inserted at a specified index.

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

var out = toInsertedAt( x, 0, 5 );
// returns [ 5, 1, 2, 3, 4 ]

out = toInsertedAt( x, -1, 6 );
// returns [ 1, 2, 3, 4, 6 ]
```

The function accepts the following arguments:

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

### toInsertedAt.assign( x, index, value, out, stride, offset )

Copies elements from one array to another array and inserts a provided value at a specified index.

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

var out = [ 0, 0, 0, 0, 0 ];
var arr = toInsertedAt.assign( x, 0, 5, out, 1, 0 );
// returns [ 5, 1, 2, 3, 4 ]

var bool = ( arr === out );
// returns true
```

The function accepts the following arguments:

-   **x**: an input array.
-   **index**: element index.
-   **value**: value to insert.
-   **out**: output array.
-   **stride**: output array stride.
-   **offset**: output array offset.

</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

-   Negative indices are resolved relative to the last array element, with the last element corresponding to `-1`.

</section>

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<!-- Package usage examples. -->

<section class="examples">

## Examples

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

```javascript
var discreteUniform = require( '@stdlib/random-array-discrete-uniform' );
var toInsertedAt = require( '@stdlib/array-base-to-inserted-at' );

// Define an array:
var opts = {
    'dtype': 'generic'
};
var x = discreteUniform( 5, -100, 100, opts );

// Define an array containing random index values:
var indices = discreteUniform( 100, -x.length, x.length, opts );

// Define an array with random values to insert:
var values = discreteUniform( indices.length, -10000, 10000, opts );

// Randomly insert elements in the input array:
var i;
for ( i = 0; i < indices.length; i++ ) {
    console.log( 'x = [%s]', toInsertedAt( x, indices[ i ], values[ i ] ).join( ',' ) );
}
```

</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

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---

## License

See [LICENSE][stdlib-license].


## Copyright

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

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