@stdlib/stats-base-dists-weibull-median
v0.2.2
Published
Weibull distribution median.
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Median
The median for a Weibull random variable is
where lambda > 0
is the shape parameter and k > 0
is the scale parameter.
Installation
npm install @stdlib/stats-base-dists-weibull-median
Usage
var median = require( '@stdlib/stats-base-dists-weibull-median' );
median( k, lambda )
Returns the median of a Weibull distribution with parameters k
(shape parameter) and lambda
(scale parameter).
var v = median( 1.0, 1.0 );
// returns ~0.693
v = median( 4.0, 12.0 );
// returns ~10.949
v = median( 8.0, 2.0 );
// returns ~1.91
If provided NaN
as any argument, the function returns NaN
.
var v = median( NaN, 2.0 );
// returns NaN
v = median( 2.0, NaN );
// returns NaN
If provided k <= 0
, the function returns NaN
.
var v = median( 0.0, 1.0 );
// returns NaN
v = median( -1.0, 1.0 );
// returns NaN
If provided lambda <= 0
, the function returns NaN
.
var v = median( 1.0, 0.0 );
// returns NaN
v = median( 1.0, -1.0 );
// returns NaN
Examples
var randu = require( '@stdlib/random-base-randu' );
var EPS = require( '@stdlib/constants-float64-eps' );
var median = require( '@stdlib/stats-base-dists-weibull-median' );
var lambda;
var k;
var v;
var i;
for ( i = 0; i < 10; i++ ) {
k = ( randu()*10.0 ) + EPS;
lambda = ( randu()*10.0 ) + EPS;
v = median( k, lambda );
console.log( 'k: %d, λ: %d, Median(X;k,λ): %d', k.toFixed( 4 ), lambda.toFixed( 4 ), v.toFixed( 4 ) );
}
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.