npm package: @stdlib/stats-base-dists-planck
Description: Planck distribution.
Author: The Stdlib Authors
Latest version: 0.1.1

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# Planck

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

> Planck distribution.

<section class="installation">

## Installation

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

</section>

<section class="usage">

## Usage

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

#### planck

Planck distribution.

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

The namespace contains the following distribution functions:

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

<div class="namespace-toc">

-   <span class="signature">[`cdf( x, lambda )`][@stdlib/stats/base/dists/planck/cdf]</span><span class="delimiter">: </span><span class="description">planck (discrete exponential) distribution cumulative distribution function.</span>
-   <span class="signature">[`logcdf( x, lambda )`][@stdlib/stats/base/dists/planck/logcdf]</span><span class="delimiter">: </span><span class="description">evaluate the logarithm of the cumulative distribution function for a Planck (discrete exponential) distribution.</span>
-   <span class="signature">[`logpmf( x, lambda )`][@stdlib/stats/base/dists/planck/logpmf]</span><span class="delimiter">: </span><span class="description">evaluate the logarithm of the probability mass function (PMF) for a Planck (discrete exponential) distribution.</span>
-   <span class="signature">[`mgf( t, lambda )`][@stdlib/stats/base/dists/planck/mgf]</span><span class="delimiter">: </span><span class="description">planck (discrete exponential) distribution moment-generating function (MGF).</span>
-   <span class="signature">[`pmf( x, lambda )`][@stdlib/stats/base/dists/planck/pmf]</span><span class="delimiter">: </span><span class="description">planck (discrete exponential) distribution probability mass function (PMF).</span>
-   <span class="signature">[`quantile( p, lambda )`][@stdlib/stats/base/dists/planck/quantile]</span><span class="delimiter">: </span><span class="description">planck (discrete exponential) 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( lambda )`][@stdlib/stats/base/dists/planck/entropy]</span><span class="delimiter">: </span><span class="description">planck (discrete exponential) distribution differential entropy.</span>
-   <span class="signature">[`kurtosis( lambda )`][@stdlib/stats/base/dists/planck/kurtosis]</span><span class="delimiter">: </span><span class="description">planck (discrete exponential) distribution excess kurtosis.</span>
-   <span class="signature">[`mean( lambda )`][@stdlib/stats/base/dists/planck/mean]</span><span class="delimiter">: </span><span class="description">planck distribution expected value.</span>
-   <span class="signature">[`median( lambda )`][@stdlib/stats/base/dists/planck/median]</span><span class="delimiter">: </span><span class="description">planck (discrete exponential) distribution median.</span>
-   <span class="signature">[`mode( lambda )`][@stdlib/stats/base/dists/planck/mode]</span><span class="delimiter">: </span><span class="description">planck (discrete exponential) distribution mode.</span>
-   <span class="signature">[`skewness( lambda )`][@stdlib/stats/base/dists/planck/skewness]</span><span class="delimiter">: </span><span class="description">planck (discrete exponential) distribution skewness.</span>
-   <span class="signature">[`stdev( lambda )`][@stdlib/stats/base/dists/planck/stdev]</span><span class="delimiter">: </span><span class="description">planck distribution standard deviation.</span>
-   <span class="signature">[`variance( lambda )`][@stdlib/stats/base/dists/planck/variance]</span><span class="delimiter">: </span><span class="description">planck distribution variance.</span>

</div>

<!-- </toc> -->

</section>

<!-- /.usage -->

<section class="examples">

## Examples

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

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

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

</section>

<!-- /.examples -->

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

<section class="related">

</section>

<!-- /.related -->

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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].

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---

## License

See [LICENSE][stdlib-license].


## Copyright

Copyright &copy; 2016-2026. The Stdlib [Authors][stdlib-authors].

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

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

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

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

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

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

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

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

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

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

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

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

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

</section>

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