@stdlib/stats-base-dists-poisson NPM

Poisson

Poisson distribution.

Installation

npm install @stdlib/stats-base-dists-poisson

Usage

var poisson = require( '@stdlib/stats-base-dists-poisson' );

poisson

Poisson distribution.

var dist = poisson;
// returns {...}

The namespace contains the following distribution functions:

cdf( x, lambda ): Poisson distribution cumulative distribution function.
logpmf( x, lambda ): evaluate the natural logarithm of the probability mass function (PMF) for a Poisson distribution.
mgf( t, lambda ): Poisson distribution moment-generating function (MGF).
pmf( x, lambda ): Poisson distribution probability mass function (PMF).
quantile( p, lambda ): Poisson distribution quantile function.

The namespace contains the following functions for calculating distribution properties:

entropy( lambda ): Poisson distribution entropy.
kurtosis( lambda ): Poisson distribution excess kurtosis.
mean( lambda ): Poisson distribution expected value.
median( lambda ): Poisson distribution median.
mode( lambda ): Poisson distribution mode.
skewness( lambda ): Poisson distribution skewness.
stdev( lambda ): Poisson distribution standard deviation.
variance( lambda ): Poisson distribution variance.

The namespace contains a constructor function for creating a Poisson distribution object.

Poisson( [lambda] ): Poisson distribution constructor.

var Poisson = require( '@stdlib/stats-base-dists-poisson' ).Poisson;

var dist = new Poisson( 2.0 );

var y = dist.pmf( 3.0 );
// returns ~0.18

y = dist.pmf( 2.3 );
// returns 0.0

Examples

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

console.log( objectKeys( poisson ) );

Notice

This package is part of 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, see the main project repository.