Package weka.core

Class SpecialFunctions

java.lang.Object
weka.core.SpecialFunctions
All Implemented Interfaces:
RevisionHandler
public final class SpecialFunctions extends Object implements RevisionHandler
Class implementing some mathematical functions.
Version:
$Revision: 14911 $
Author:
Eibe Frank (eibe@cs.waikato.ac.nz)

  • Constructor Summary

    Constructors
    Constructor
    Description
    SpecialFunctions()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    String
    getRevision()
    Returns the revision string.
    static double
    lnFactorial(double x)
    Returns natural logarithm of factorial using gamma function.
    static double
    log2Binomial(double a, double b)
    Returns base 2 logarithm of binomial coefficient using gamma function.
    static double
    log2Multinomial(double a, double[] bs)
    Returns base 2 logarithm of multinomial using gamma function.
    static void
    main(String[] ops)
    Main method for testing this class.

    Methods inherited from class java.lang.Object

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

  • Constructor Details

    • SpecialFunctions

      public SpecialFunctions()

  • Method Details

    • lnFactorial

      public static double lnFactorial(double x)
      Returns natural logarithm of factorial using gamma function.
      Parameters:
      x - the value
      Returns:
      natural logarithm of factorial

    • log2Binomial

      public static double log2Binomial(double a, double b)
      Returns base 2 logarithm of binomial coefficient using gamma function.
      Parameters:
      a - upper part of binomial coefficient
      b - lower part
      Returns:
      the base 2 logarithm of the binominal coefficient a over b

    • log2Multinomial

      public static double log2Multinomial(double a, double[] bs)
      Returns base 2 logarithm of multinomial using gamma function.
      Parameters:
      a - upper part of multinomial coefficient
      bs - lower part
      Returns:
      multinomial coefficient of a over the bs

    • getRevision

      public String getRevision()
      Returns the revision string.
      Specified by:
      getRevision in interface RevisionHandler
      Returns:
      the revision

    • main

      public static void main(String[] ops)
      Main method for testing this class.