Mean

Lévy distribution expected value.

The expected value for a Lévy random variable with location μ and scale c > 0 is

Installation

npm install @stdlib/stats-base-dists-levy-mean

Usage

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

mean( mu, c )

Returns the expected value for a Lévy distribution with location parameter mu and scale parameter c.

var y = mean( 2.0, 1.0 );
// returns Infinity

y = mean( 0.0, 1.0 );
// returns Infinity

y = mean( -1.0, 4.0 );
// returns Infinity

If provided NaN as any argument, the function returns NaN.

var y = mean( NaN, 1.0 );
// returns NaN

y = mean( 0.0, NaN );
// returns NaN

If provided c <= 0, the function returns NaN.

var y = mean( 0.0, 0.0 );
// returns NaN

y = mean( 0.0, -1.0 );
// returns NaN

Examples

var randu = require( '@stdlib/random-base-randu' );
var mean = require( '@stdlib/stats-base-dists-levy-mean' );

var mu;
var c;
var y;
var i;

for ( i = 0; i < 10; i++ ) {
    mu = ( randu()*10.0 ) - 5.0;
    c = randu() * 20.0;
    y = mean( mu, c );
    console.log( 'µ: %d, c: %d, E(X;µ,c): %d', mu.toFixed( 4 ), c.toFixed( 4 ), y.toFixed( 4 ) );
}

C APIs

Usage

#include "stdlib/stats/base/dists/levy/mean.h"

stdlib_base_dists_levy_mean( mu, c )

Evaluates the expected value for a Lévy distribution with location parameter mu and scale parameter c.

double out = stdlib_base_dists_levy_mean( 0.0, 1.0 );
// returns Infinity

The function accepts the following arguments:

• mu: [in] double location parameter.
• c: [in] double scale parameter.

double stdlib_base_dists_levy_mean( const double mu, const double c );

Examples

#include "stdlib/stats/base/dists/levy/mean.h"
#include <stdlib.h>
#include <stdio.h>

static double random_uniform( const double min, const double max ) {
    double v = (double)rand() / ( (double)RAND_MAX + 1.0 );
    return min + ( v*(max-min) );
}

int main( void ) {
    double mu;
    double c;
    double y;
    int i;

    for ( i = 0; i < 25; i++ ) {
        x = random_uniform( -5.0, 5.0 );
        a = random_uniform( 0.0, 20.0 );
        y = stdlib_base_dists_levy_mean( mu, c );
        printf( "µ: %lf, c: %lf, E(X;µ,c): %lf\n", mu, c, 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.