Logarithm of Probability Mass Function

Evaluate the natural logarithm of the probability mass function (PMF) for a degenerate distribution.

Installation

npm install @stdlib/stats-base-dists-degenerate-logpmf

Usage

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

logpmf( x, mu )

Evaluates the natural logarithm of the PMF for a degenerate distribution centered at mu.

var y = logpmf( 2.0, 8.0 );
// returns -Infinity

y = logpmf( 8.0, 8.0 );
// returns 0.0

logpmf.factory( mu )

Returns a function for evaluating the natural logarithm of the PMF of a degenerate distribution centered at mu.

var mylogpmf = logpmf.factory( 10.0 );

var y = mylogpmf( 10.0 );
// returns 0.0

y = mylogpmf( 5.0 );
// returns -Infinity

y = mylogpmf( 12.0 );
// returns -Infinity

Examples

var randu = require( '@stdlib/random-base-randu' );
var round = require( '@stdlib/math-base-special-round' );
var logpmf = require( '@stdlib/stats-base-dists-degenerate-logpmf' );

var mu;
var x;
var y;
var i;

for ( i = 0; i < 100; i++ ) {
    x = round( randu()*5.0 );
    mu = round( randu()*5.0 );
    y = logpmf( x, mu );
    console.log( 'x: %d, µ: %d, ln(P(X=x;µ)): %d', x, mu, y );
}

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.

Community

License

See LICENSE.

Copyright

Copyright © 2016-2024. The Stdlib Authors.