Entropy

Bernoulli distribution entropy.

The entropy (in nats) for a Bernoulli random variable is

where p is the success probability and q = 1 - p.

Installation

npm install @stdlib/stats-base-dists-bernoulli-entropy

Usage

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

entropy( p )

Returns the entropy of a Bernoulli distribution with success probability p (in nats).

var v = entropy( 0.1 );
// returns ~0.325

v = entropy( 0.5 );
// returns ~0.693

If provided a success probability p outside of [0,1], the function returns NaN.

var v = entropy( NaN );
// returns NaN

v = entropy( 1.5 );
// returns NaN

v = entropy( -1.0 );
// returns NaN

Examples

var uniform = require( '@stdlib/random-array-uniform' );
var logEachMap = require( '@stdlib/console-log-each-map' );
var entropy = require( '@stdlib/stats-base-dists-bernoulli-entropy' );

var opts = {
    'dtype': 'float64'
};
var p = uniform( 25, 0.0, 1.0, opts );

logEachMap( 'p: %0.4f, H(X;p): %0.4f', p, entropy );

C APIs

Usage

#include "stdlib/stats/base/dists/bernoulli/entropy.h"

stdlib_base_dists_bernoulli_entropy( p )

Returns the entropy of a Bernoulli distribution with success probability p (in nats).

double out = stdlib_base_dists_bernoulli_entropy( 0.1 );
// returns ~0.325

The function accepts the following arguments:

• p: [in] double success probability.

double stdlib_base_dists_bernoulli_entropy( const double p );

Examples

#include "stdlib/stats/base/dists/bernoulli/entropy.h"
#include <stdlib.h>
#include <stdio.h>

int main( void ) {
    double p;
    double y;
    int i;

    for ( i = 0; i < 25; i++ ) {
        p = (double)rand() / ( (double)RAND_MAX + 1.0 );
        y = stdlib_base_dists_bernoulli_entropy( p );
        printf( "x: %lf, H(X;p): %lf\n", p, 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 © 2016-2026. The Stdlib Authors.