net.sf.doodleproject.numerics4j.special
Class Beta

java.lang.Object
  net.sf.doodleproject.numerics4j.special.Beta

public final class Beta
extends java.lang.Object

Utility class that provides methods related to the beta family of functions.

Version:

$Revision: 1.2 $ $Date: 2007/10/25 04:44:14 $

Method Summary

static double	logBeta(double a, double b) Returns the natural logarithm of the beta function B(a, b) (1).
static double	regularizedBeta(double x, double a, double b) Returns the regularized beta function Ix(a, b) (1).

Methods inherited from class java.lang.Object

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

Method Detail

logBeta

public static double logBeta(double a,
                             double b)

Returns the natural logarithm of the beta function B(a, b) (1).

References:

1. Eric W. Weisstein. "Beta Function." From MathWorld--A Wolfram Web Resource. http://mathworld.wolfram.com/BetaFunction.html

Parameters:

a - the a parameter.

b - the b parameter.

Returns:

log(B(a, b))

regularizedBeta

public static double regularizedBeta(double x,
                                     double a,
                                     double b)
                              throws NumericException

Returns the regularized beta function I_x(a, b) (1).

References:

1. Eric W. Weisstein. "Regularized Beta Function." From MathWorld--A Wolfram Web Resource. http://mathworld.wolfram.com/RegularizedBetaFunction.html

Parameters:

x - the evaluation point.

a - the a parameter.

b - the b parameter.

Returns:

I_x(a, b)

Throws:

NumericException - if the value could not be computed.