npm package: @stdlib/array-base-count-same-value
Description: Count the number of elements in an array that are equal to a specified value.
Author: The Stdlib Authors
Latest version: 0.2.2

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  <summary>
    About stdlib...
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# countSameValue

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

> Count the number of elements in an array that are equal to a specified value.

<!-- Section to include introductory text. Make sure to keep an empty line after the intro `section` element and another before the `/section` close. -->

<section class="intro">

</section>

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<!-- Package usage documentation. -->

<section class="installation">

## Installation

```bash
npm install @stdlib/array-base-count-same-value
```

</section>

<section class="usage">

## Usage

```javascript
var countSameValue = require( '@stdlib/array-base-count-same-value' );
```

#### countSameValue( x, value )

Counts the number of elements in an array that are equal to a specified value.

```javascript
var x = [ 0, 1, 0, 1, 2 ];

var out = countSameValue( x, 1 );
// returns 2
```

In contrast to an implementation using the strict equality operator `===`, the function distinguishes between `+0` and `-0` and treats `NaNs` as the same value.

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

var out = countSameValue( x, NaN );
// returns 3
```

</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

-   The function uses the [SameValue Algorithm][@stdlib/assert/is-same-value] as specified in ECMAScript 5.

</section>

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<!-- Package usage examples. -->

<section class="examples">

## Examples

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

```javascript
var bernoulli = require( '@stdlib/random-array-bernoulli' );
var countSameValue = require( '@stdlib/array-base-count-same-value' );

var x = bernoulli( 10, 0.5, {
    'dtype': 'generic'
});
console.log( x );

var n = countSameValue( x, 1 );
console.log( n );
```

</section>

<!-- /.examples -->

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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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[umd]: https://github.com/umdjs/umd
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[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/array-base-count-same-value/main/LICENSE

[@stdlib/assert/is-same-value]: https://www.npmjs.com/package/@stdlib/assert-is-same-value

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