npm package: @stdlib/stats-base-dists-beta
Description: Beta distribution.
Author: The Stdlib Authors
Latest version: 0.3.1

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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>

# Beta

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

> Beta distribution.

<section class="installation">

## Installation

```bash
npm install @stdlib/stats-base-dists-beta
```

</section>

<section class="usage">

## Usage

```javascript
var beta = require( '@stdlib/stats-base-dists-beta' );
```

#### beta

[Beta][beta-distribution] distribution.

```javascript
var dist = beta;
// returns {...}
```

The namespace contains the following distribution functions:

<!-- <toc pattern="*+(cdf|pdf|mgf|quantile)*"> -->

<div class="namespace-toc">

-   <span class="signature">[`cdf( x, alpha, beta )`][@stdlib/stats/base/dists/beta/cdf]</span><span class="delimiter">: </span><span class="description">beta distribution cumulative distribution function.</span>
-   <span class="signature">[`logcdf( x, alpha, beta )`][@stdlib/stats/base/dists/beta/logcdf]</span><span class="delimiter">: </span><span class="description">beta distribution logarithm of cumulative distribution function.</span>
-   <span class="signature">[`logpdf( x, alpha, beta )`][@stdlib/stats/base/dists/beta/logpdf]</span><span class="delimiter">: </span><span class="description">beta distribution logarithm of probability density function (PDF).</span>
-   <span class="signature">[`mgf( t, alpha, beta )`][@stdlib/stats/base/dists/beta/mgf]</span><span class="delimiter">: </span><span class="description">beta distribution moment-generating function (MGF).</span>
-   <span class="signature">[`pdf( x, alpha, beta )`][@stdlib/stats/base/dists/beta/pdf]</span><span class="delimiter">: </span><span class="description">beta distribution probability density function (PDF).</span>
-   <span class="signature">[`quantile( p, alpha, beta )`][@stdlib/stats/base/dists/beta/quantile]</span><span class="delimiter">: </span><span class="description">beta distribution quantile function.</span>

</div>

<!-- </toc> -->

The namespace contains the following functions for calculating distribution properties:

<!-- <toc pattern="*+(entropy|kurtosis|mean|median|mode|skewness|stdev|variance)*"> -->

<div class="namespace-toc">

-   <span class="signature">[`entropy( alpha, beta )`][@stdlib/stats/base/dists/beta/entropy]</span><span class="delimiter">: </span><span class="description">beta distribution differential entropy.</span>
-   <span class="signature">[`kurtosis( alpha, beta )`][@stdlib/stats/base/dists/beta/kurtosis]</span><span class="delimiter">: </span><span class="description">beta distribution excess kurtosis.</span>
-   <span class="signature">[`mean( alpha, beta )`][@stdlib/stats/base/dists/beta/mean]</span><span class="delimiter">: </span><span class="description">beta distribution expected value.</span>
-   <span class="signature">[`median( alpha, beta )`][@stdlib/stats/base/dists/beta/median]</span><span class="delimiter">: </span><span class="description">beta distribution median.</span>
-   <span class="signature">[`mode( alpha, beta )`][@stdlib/stats/base/dists/beta/mode]</span><span class="delimiter">: </span><span class="description">beta distribution mode.</span>
-   <span class="signature">[`skewness( alpha, beta )`][@stdlib/stats/base/dists/beta/skewness]</span><span class="delimiter">: </span><span class="description">beta distribution skewness.</span>
-   <span class="signature">[`stdev( alpha, beta )`][@stdlib/stats/base/dists/beta/stdev]</span><span class="delimiter">: </span><span class="description">beta distribution standard deviation.</span>
-   <span class="signature">[`variance( alpha, beta )`][@stdlib/stats/base/dists/beta/variance]</span><span class="delimiter">: </span><span class="description">beta distribution variance.</span>

</div>

<!-- </toc> -->

The namespace contains a constructor function for creating a [beta][beta-distribution] distribution object.

<!-- <toc pattern="*ctor*"> -->

<div class="namespace-toc">

-   <span class="signature">[`Beta( [alpha, beta] )`][@stdlib/stats/base/dists/beta/ctor]</span><span class="delimiter">: </span><span class="description">beta distribution constructor.</span>

</div>

<!-- </toc> -->

```javascript
var Beta = require( '@stdlib/stats-base-dists-beta' ).Beta;
var dist = new Beta( 2.0, 4.0 );

var mu = dist.mean;
// returns ~0.333
```

</section>

<!-- /.usage -->

<section class="examples">

## Examples

<!-- TODO: better examples -->

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

```javascript
var objectKeys = require( '@stdlib/utils-keys' );
var beta = require( '@stdlib/stats-base-dists-beta' );

console.log( objectKeys( beta ) );
```

</section>

<!-- /.examples -->

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

<section class="related">

</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-base-dists-beta.svg
[npm-url]: https://npmjs.org/package/@stdlib/stats-base-dists-beta

[test-image]: https://github.com/stdlib-js/stats-base-dists-beta/actions/workflows/test.yml/badge.svg?branch=v0.3.1
[test-url]: https://github.com/stdlib-js/stats-base-dists-beta/actions/workflows/test.yml?query=branch:v0.3.1

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

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

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

[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/stats-base-dists-beta/main/LICENSE

[beta-distribution]: https://en.wikipedia.org/wiki/Beta_distribution

<!-- <toc-links> -->

[@stdlib/stats/base/dists/beta/ctor]: https://www.npmjs.com/package/@stdlib/stats-base-dists-beta-ctor

[@stdlib/stats/base/dists/beta/entropy]: https://www.npmjs.com/package/@stdlib/stats-base-dists-beta-entropy

[@stdlib/stats/base/dists/beta/kurtosis]: https://www.npmjs.com/package/@stdlib/stats-base-dists-beta-kurtosis

[@stdlib/stats/base/dists/beta/mean]: https://www.npmjs.com/package/@stdlib/stats-base-dists-beta-mean

[@stdlib/stats/base/dists/beta/median]: https://www.npmjs.com/package/@stdlib/stats-base-dists-beta-median

[@stdlib/stats/base/dists/beta/mode]: https://www.npmjs.com/package/@stdlib/stats-base-dists-beta-mode

[@stdlib/stats/base/dists/beta/skewness]: https://www.npmjs.com/package/@stdlib/stats-base-dists-beta-skewness

[@stdlib/stats/base/dists/beta/stdev]: https://www.npmjs.com/package/@stdlib/stats-base-dists-beta-stdev

[@stdlib/stats/base/dists/beta/variance]: https://www.npmjs.com/package/@stdlib/stats-base-dists-beta-variance

[@stdlib/stats/base/dists/beta/cdf]: https://www.npmjs.com/package/@stdlib/stats-base-dists-beta-cdf

[@stdlib/stats/base/dists/beta/logcdf]: https://www.npmjs.com/package/@stdlib/stats-base-dists-beta-logcdf

[@stdlib/stats/base/dists/beta/logpdf]: https://www.npmjs.com/package/@stdlib/stats-base-dists-beta-logpdf

[@stdlib/stats/base/dists/beta/mgf]: https://www.npmjs.com/package/@stdlib/stats-base-dists-beta-mgf

[@stdlib/stats/base/dists/beta/pdf]: https://www.npmjs.com/package/@stdlib/stats-base-dists-beta-pdf

[@stdlib/stats/base/dists/beta/quantile]: https://www.npmjs.com/package/@stdlib/stats-base-dists-beta-quantile

<!-- </toc-links> -->

</section>

<!-- /.links -->