Rayleigh
Rayleigh distribution constructor.
Usage
var Rayleigh = require( '@stdlib/stats/base/dists/rayleigh/ctor' );
Rayleigh( [sigma] )
Returns an Rayleigh distribution object.
var rayleigh = new Rayleigh();
var mu = rayleigh.mean;
// returns ~1.253
By default, sigma = 1.0
. To create a distribution having a different scale parameter sigma
, provide a parameter value.
var rayleigh = new Rayleigh( 4.0 );
var mu = rayleigh.mean;
// returns ~5.013
rayleigh
A Rayleigh distribution object has the following properties and methods...
Writable Properties
rayleigh.sigma
Scale parameter of the distribution. sigma
must be a positive number.
var rayleigh = new Rayleigh( 2.0 );
var sigma = rayleigh.sigma;
// returns 2.0
rayleigh.sigma = 3.0;
sigma = rayleigh.sigma;
// returns 3.0
Computed Properties
Rayleigh.prototype.entropy
Returns the differential entropy.
var rayleigh = new Rayleigh( 4.0 );
var entropy = rayleigh.entropy;
// returns ~2.328
Rayleigh.prototype.kurtosis
Returns the excess kurtosis.
var rayleigh = new Rayleigh( 4.0 );
var kurtosis = rayleigh.kurtosis;
// returns ~0.245
Rayleigh.prototype.mean
Returns the median.
var rayleigh = new Rayleigh( 4.0 );
var mu = rayleigh.mean;
// returns ~5.013
Rayleigh.prototype.median
Returns the median.
var rayleigh = new Rayleigh( 4.0 );
var median = rayleigh.median;
// returns ~4.71
Rayleigh.prototype.mode
Returns the mode.
var rayleigh = new Rayleigh( 4.0 );
var mode = rayleigh.mode;
// returns 4.0
Rayleigh.prototype.skewness
Returns the skewness.
var rayleigh = new Rayleigh( 4.0 );
var skewness = rayleigh.skewness;
// returns ~0.631
Rayleigh.prototype.stdev
Returns the standard deviation.
var rayleigh = new Rayleigh( 4.0 );
var s = rayleigh.stdev;
// returns ~2.62
Rayleigh.prototype.variance
Returns the variance.
var rayleigh = new Rayleigh( 4.0 );
var s2 = rayleigh.variance;
// returns ~6.867
Methods
Rayleigh.prototype.cdf( x )
Evaluates the cumulative distribution function (CDF).
var rayleigh = new Rayleigh( 2.0 );
var y = rayleigh.cdf( 1.5 );
// returns ~0.245
Rayleigh.prototype.logcdf( x )
Evaluates the natural logarithm of the cumulative distribution function (CDF).
var rayleigh = new Rayleigh( 2.0 );
var y = rayleigh.logcdf( 1.5 );
// returns ~-1.406
Rayleigh.prototype.logpdf( x )
Evaluates the natural logarithm of the probability density function (PDF).
var rayleigh = new Rayleigh( 2.0 );
var y = rayleigh.logpdf( 0.8 );
// returns ~-1.689
Rayleigh.prototype.mgf( t )
Evaluates the moment-generating function (MGF).
var rayleigh = new Rayleigh( 2.0 );
var y = rayleigh.mgf( 0.5 );
// returns ~5.586
Rayleigh.prototype.pdf( x )
Evaluates the probability density function (PDF).
var rayleigh = new Rayleigh( 2.0 );
var y = rayleigh.pdf( 0.8 );
// returns ~0.185
Rayleigh.prototype.quantile( p )
Evaluates the quantile function at probability p
.
var rayleigh = new Rayleigh( 2.0 );
var y = rayleigh.quantile( 0.5 );
// returns ~2.355
y = rayleigh.quantile( 1.9 );
// returns NaN
Examples
var Rayleigh = require( '@stdlib/stats/base/dists/rayleigh/ctor' );
var rayleigh = new Rayleigh( 2.0, 4.0 );
var mu = rayleigh.mean;
// returns ~2.507
var mode = rayleigh.mode;
// returns 2.0
var s2 = rayleigh.variance;
// returns ~1.717
var y = rayleigh.cdf( 0.8 );
// returns ~0.077