de.lmu.ifi.dbs.elki.math.statistics.distribution

Class ChiSquaredDistribution

java.lang.Object

de.lmu.ifi.dbs.elki.math.statistics.distribution.GammaDistribution

de.lmu.ifi.dbs.elki.math.statistics.distribution.ChiSquaredDistribution

All Implemented Interfaces:

Distribution

public class ChiSquaredDistribution
extends GammaDistribution

Chi-Squared distribution (a specialization of the Gamma distribution).

Field Summary

Fields inherited from class de.lmu.ifi.dbs.elki.math.statistics.distribution.GammaDistribution

LANCZOS, NUM_PRECISION

Constructor Summary

Constructors

Constructor and Description
ChiSquaredDistribution(double dof) Constructor.

Method Summary

Methods

Modifier and Type	Method and Description
static double	cdf(double val, double dof) The CDF, static version.
static double	pdf(double x, double dof) Chi-Squared distribution PDF (with 0.0 for x < 0)

Methods inherited from class de.lmu.ifi.dbs.elki.math.statistics.distribution.GammaDistribution

cdf, cdf, getK, getTheta, logGamma, nextRandom, nextRandom, pdf, pdf, regularizedGammaP, regularizedGammaQ, toString

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

ChiSquaredDistribution

public ChiSquaredDistribution(double dof)

Constructor.

Parameters:

dof - Degrees of freedom.

Method Detail

cdf

public static double cdf(double val,
         double dof)

The CDF, static version.

Parameters:

val - Value

dof - Degrees of freedom.

Returns:

cdf value

pdf

public static double pdf(double x,
         double dof)

Chi-Squared distribution PDF (with 0.0 for x < 0)

Parameters:

x - query value

dof - Degrees of freedom.

Returns:

probability density