Skewness

Chi distribution skewness.

The skewness for a chi random variable with degrees of freedom.k is

where μ is the mean of the distribution and σ its standard deviation.

Installation

npm install @stdlib/stats-base-dists-chi-skewness

Usage

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

skewness( k )

Returns the skewness of a chi distribution with degrees of freedom k.

var v = skewness( 9.0 );
// returns ~0.252

v = skewness( 0.5 );
// returns ~1.544

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

var v = skewness( -1.0 );
// returns NaN

Examples

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

var opts = {
    'dtype': 'float64'
};
var k = uniform( 10, 0.0, 20.0, opts );

logEachMap( 'k: %0.4f, skew(X;k): %0.4f', k, skewness );

C APIs

Usage

#include "stdlib/stats/base/dists/chi/skewness.h"

stdlib_base_dists_chi_skewness( k )

Returns the skewness of a chi distribution with degrees of freedom k.

double out = stdlib_base_dists_chi_skewness( 9.0 );
// returns ~0.252

The function accepts the following arguments:

• k: [in] double degrees of freedom.

double stdlib_base_dists_chi_skewness( const double k );

Examples

#include "stdlib/stats/base/dists/chi/skewness.h"
#include <stdio.h>
#include <stdlib.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 k;
    double y;
    int i;

    for ( i = 0; i < 25; i++ ) {
        k = random_uniform( 1.0, 10.0 );
        y = stdlib_base_dists_chi_skewness( k );
        printf( "k: %lf, skew(X,k): %lf\n", k, 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.