com.numericalmethod.suanshu.analysis.function.special.beta

Class LogBeta

java.lang.Object

com.numericalmethod.suanshu.analysis.function.rn2r1.BivariateRealFunction

com.numericalmethod.suanshu.analysis.function.special.beta.LogBeta

All Implemented Interfaces:

Function<Vector,java.lang.Double>, RealScalarFunction, java.io.Serializable

public class LogBeta
extends BivariateRealFunction

This class represents the log of Beta function log(B(x, y)).

                       Γ(x)Γ(y)
 log(B(x, y)) = log ( ----------- ) = logΓ(x) + logΓ(y) - logΓ(x + y)
                        Γ(x+y)
 

x > 0, y > 0

The R equivalent function is lbeta.

See Also:

Wikipedia: Beta function, Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from interface com.numericalmethod.suanshu.analysis.function.Function

Function.EvaluationException

Constructor Summary

Constructors

Constructor and Description
LogBeta()

Method Summary

Modifier and Type	Method and Description
double	evaluate(double x, double y) Compute log(B(x,y)).

Methods inherited from class com.numericalmethod.suanshu.analysis.function.rn2r1.BivariateRealFunction

dimensionOfDomain, dimensionOfRange, evaluate

Methods inherited from class java.lang.Object

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

Constructor Detail

LogBeta

public LogBeta()

Method Detail

evaluate

public double evaluate(double x,
                       double y)

Compute log(B(x,y)).

Specified by:

evaluate in class BivariateRealFunction

Parameters:

x - x >= 0

y - y >= 0

Returns:

log(B(x,y))