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

java.lang.Object
  com.numericalmethod.suanshu.analysis.function.rn2r1.BivariateRealFunction
      com.numericalmethod.suanshu.analysis.function.special.LogBeta

All Implemented Interfaces:

Function, RealScalarFunction

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

Nested Class Summary

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

Function.EvaluationException

Constructor Summary

LogBeta()

Method Summary

double

evaluate(double x, double y) Compute log(B(x, y)).

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

dimension4Domain, dimension4Range, 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))