@stdlib/stats/base/dists/lognormal/README.md

Standard library statistical functions.

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# Lognormal

> Lognormal distribution.

<section class="usage">

## Usage

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

#### lognormal

Lognormal distribution.

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

The namespace contains the following distribution functions:

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<div class="namespace-toc">

-   <span class="signature">[`cdf( x, mu, sigma )`][@stdlib/stats/base/dists/lognormal/cdf]</span><span class="delimiter">: </span><span class="description">lognormal distribution cumulative distribution function.</span>
-   <span class="signature">[`logcdf( x, mu, sigma )`][@stdlib/stats/base/dists/lognormal/logcdf]</span><span class="delimiter">: </span><span class="description">evaluate the natural logarithm of the cumulative distribution function (CDF) for a lognormal distribution.</span>
-   <span class="signature">[`logpdf( x, mu, sigma )`][@stdlib/stats/base/dists/lognormal/logpdf]</span><span class="delimiter">: </span><span class="description">evaluate the natural logarithm of the probability density function (PDF) for a lognormal distribution.</span>
-   <span class="signature">[`pdf( x, mu, sigma )`][@stdlib/stats/base/dists/lognormal/pdf]</span><span class="delimiter">: </span><span class="description">lognormal distribution probability density function (PDF).</span>
-   <span class="signature">[`quantile( p, mu, sigma )`][@stdlib/stats/base/dists/lognormal/quantile]</span><span class="delimiter">: </span><span class="description">lognormal distribution quantile function.</span>

</div>

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The namespace contains the following functions for calculating distribution properties:

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<div class="namespace-toc">

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

</div>

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

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<div class="namespace-toc">

-   <span class="signature">[`LogNormal( [mu, sigma] )`][@stdlib/stats/base/dists/lognormal/ctor]</span><span class="delimiter">: </span><span class="description">lognormal distribution constructor.</span>

</div>

<!-- </toc> -->

```javascript
var LogNormal = require( '@stdlib/stats/base/dists/lognormal' ).LogNormal;

var dist = new LogNormal( 2.0, 4.0 );

var y = dist.cdf( 0.5 );
// returns ~0.25
```

</section>

<!-- /.usage -->

<section class="examples">

## Examples

<!-- TODO: better examples -->

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

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

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

</section>

<!-- /.examples -->

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

<section class="related">

</section>

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<section class="links">

[lognormal-distribution]: https://en.wikipedia.org/wiki/Log-normal_distribution

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[@stdlib/stats/base/dists/lognormal/ctor]: https://github.com/stdlib-js/stats/tree/main/base/dists/lognormal/ctor

[@stdlib/stats/base/dists/lognormal/entropy]: https://github.com/stdlib-js/stats/tree/main/base/dists/lognormal/entropy

[@stdlib/stats/base/dists/lognormal/kurtosis]: https://github.com/stdlib-js/stats/tree/main/base/dists/lognormal/kurtosis

[@stdlib/stats/base/dists/lognormal/mean]: https://github.com/stdlib-js/stats/tree/main/base/dists/lognormal/mean

[@stdlib/stats/base/dists/lognormal/median]: https://github.com/stdlib-js/stats/tree/main/base/dists/lognormal/median

[@stdlib/stats/base/dists/lognormal/mode]: https://github.com/stdlib-js/stats/tree/main/base/dists/lognormal/mode

[@stdlib/stats/base/dists/lognormal/skewness]: https://github.com/stdlib-js/stats/tree/main/base/dists/lognormal/skewness

[@stdlib/stats/base/dists/lognormal/stdev]: https://github.com/stdlib-js/stats/tree/main/base/dists/lognormal/stdev

[@stdlib/stats/base/dists/lognormal/variance]: https://github.com/stdlib-js/stats/tree/main/base/dists/lognormal/variance

[@stdlib/stats/base/dists/lognormal/cdf]: https://github.com/stdlib-js/stats/tree/main/base/dists/lognormal/cdf

[@stdlib/stats/base/dists/lognormal/logcdf]: https://github.com/stdlib-js/stats/tree/main/base/dists/lognormal/logcdf

[@stdlib/stats/base/dists/lognormal/logpdf]: https://github.com/stdlib-js/stats/tree/main/base/dists/lognormal/logpdf

[@stdlib/stats/base/dists/lognormal/pdf]: https://github.com/stdlib-js/stats/tree/main/base/dists/lognormal/pdf

[@stdlib/stats/base/dists/lognormal/quantile]: https://github.com/stdlib-js/stats/tree/main/base/dists/lognormal/quantile

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</section>

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