npm package: @stdlib/array-base-dedupe
Description: Remove consecutive duplicated values.
Author: The Stdlib Authors
Latest version: 0.2.3

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    About stdlib...
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  <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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# dedupe

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

> Remove consecutive duplicated values.

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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-dedupe
```

</section>

<section class="usage">

## Usage

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

#### dedupe( x, limit, equalNaNs )

Removes consecutive duplicated values.

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

var y = dedupe( x, 1, false );
// returns [ 1, 2, 3 ]

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

When `equalNaNs` is `false`, `NaN` values are considered distinct, and, when `equalNaNs` is `true`, `NaN` values are considered equal.

```javascript
var x = [ NaN, NaN, 2, NaN, NaN ];

var y1 = dedupe( x, 1, false );
// returns [ NaN, NaN, 2, NaN, NaN ]

var y2 = dedupe( x, 1, true );
// returns [ NaN, 2, NaN ]
```

To allow consecutive duplicate values up to a specified limit, provide a `limit` argument greater than one.

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

var y = dedupe( x, 2, false );
// returns [ 1, 1, 2, 2, 3, 3 ]
```

</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

-   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 dedupe = require( '@stdlib/array-base-dedupe' );

// Create an array of random numbers:
var x = discreteUniform( 30, 0, 5, {
    'dtype': 'generic'
});
// returns [...]

// Remove consecutive duplicates:
var y = dedupe( x, 1, false );
// returns [...]

console.log( y );
```

</section>

<!-- /.examples -->

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</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].

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[npm-url]: https://npmjs.org/package/@stdlib/array-base-dedupe

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

[coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/array-base-dedupe/main.svg
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[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-dedupe/tree/deno
[deno-readme]: https://github.com/stdlib-js/array-base-dedupe/blob/deno/README.md
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[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/array-base-dedupe/main/LICENSE

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