npm package: @stdlib/array-base-count-same-value-zero
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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# countSameValueZero

[![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.

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</section>

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<section class="installation">

## Installation

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

</section>

<section class="usage">

## Usage

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

#### countSameValueZero( 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 = countSameValueZero( x, 1 );
// returns 2
```

In contrast to an implementation using the strict equality operator `===`, the function treats `NaNs` as the same value.

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

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

In contrast to an implementation using the [SameValue Algorithm][@stdlib/array/base/count-same-value] (as specified in ECMAScript 5), the function does not distinguish between `+0` and `-0`.

```javascript
var x = [ 0.0, -0.0, 0.0 ];

var out = countSameValueZero( x, 0.0 );
// returns 3
```

</section>

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<section class="examples">

## Examples

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

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

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

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

</section>

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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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[@stdlib/array/base/count-same-value]: https://www.npmjs.com/package/@stdlib/array-base-count-same-value

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