npm package: @stdlib/stats-incr-count
Description: Compute a count incrementally.
Author: The Stdlib Authors
Latest version: 0.2.3

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<details>
  <summary>
    About stdlib...
  </summary>
  <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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</details>

# incrcount

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

> Compute a count incrementally.

<section class="installation">

## Installation

```bash
npm install @stdlib/stats-incr-count
```

</section>

<section class="usage">

## Usage

```javascript
var incrcount = require( '@stdlib/stats-incr-count' );
```

#### incrcount()

Returns an accumulator `function` which incrementally computes a count.

```javascript
var accumulator = incrcount();
```

#### accumulator( \[x] )

If provided an input value `x`, the accumulator function returns an updated count. If not provided an input value `x`, the accumulator function returns the current count.

```javascript
var accumulator = incrcount();

var count = accumulator( 2.0 );
// returns 1

count = accumulator( 1.0 );
// returns 2

count = accumulator( 3.0 );
// returns 3

count = accumulator();
// returns 3
```

</section>

<!-- /.usage -->

<section class="examples">

## Examples

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

```javascript
var randu = require( '@stdlib/random-base-randu' );
var incrcount = require( '@stdlib/stats-incr-count' );

var accumulator;
var v;
var i;

// Initialize an accumulator:
accumulator = incrcount();

// For each simulated datum, update the count...
for ( i = 0; i < 100; i++ ) {
    v = randu() * 100.0;
    accumulator( v );
}
console.log( accumulator() );
```

</section>

<!-- /.examples -->

<!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. -->

<section class="related">

* * *

## See Also

-   <span class="package-name">[`@stdlib/stats-incr/mean`][@stdlib/stats/incr/mean]</span><span class="delimiter">: </span><span class="description">compute an arithmetic mean incrementally.</span>
-   <span class="package-name">[`@stdlib/stats-incr/sum`][@stdlib/stats/incr/sum]</span><span class="delimiter">: </span><span class="description">compute a sum incrementally.</span>
-   <span class="package-name">[`@stdlib/stats-incr/summary`][@stdlib/stats/incr/summary]</span><span class="delimiter">: </span><span class="description">compute a statistical summary incrementally.</span>

</section>

<!-- /.related -->

<!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->


<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].

</section>

<!-- /.stdlib -->

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<section class="links">

[npm-image]: http://img.shields.io/npm/v/@stdlib/stats-incr-count.svg
[npm-url]: https://npmjs.org/package/@stdlib/stats-incr-count

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

[coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/stats-incr-count/main.svg
[coverage-url]: https://codecov.io/github/stdlib-js/stats-incr-count?branch=main

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

[stdlib-authors]: https://github.com/stdlib-js/stdlib/graphs/contributors

[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/stats-incr-count/tree/deno
[deno-readme]: https://github.com/stdlib-js/stats-incr-count/blob/deno/README.md
[umd-url]: https://github.com/stdlib-js/stats-incr-count/tree/umd
[umd-readme]: https://github.com/stdlib-js/stats-incr-count/blob/umd/README.md
[esm-url]: https://github.com/stdlib-js/stats-incr-count/tree/esm
[esm-readme]: https://github.com/stdlib-js/stats-incr-count/blob/esm/README.md
[branches-url]: https://github.com/stdlib-js/stats-incr-count/blob/main/branches.md

[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/stats-incr-count/main/LICENSE

<!-- <related-links> -->

[@stdlib/stats/incr/mean]: https://www.npmjs.com/package/@stdlib/stats-incr-mean

[@stdlib/stats/incr/sum]: https://www.npmjs.com/package/@stdlib/stats-incr-sum

[@stdlib/stats/incr/summary]: https://www.npmjs.com/package/@stdlib/stats-incr-summary

<!-- </related-links> -->

</section>

<!-- /.links -->