bayesnet.jayes.util

Class MathUtils

java.lang.Object

bayesnet.jayes.util.MathUtils

public final class MathUtils
extends java.lang.Object

Method Summary

Modifier and Type	Method and Description
static void	exp(double[] vector)
static void	exp(IArrayWrapper array)
static void	log(double[] vector)
static void	log(IArrayWrapper vector)
static double[]	normalize(double[] vector)
static double[]	normalizeLog(double[] vector)
static int	product(int[] vector)
static int	productOfRange(int[] vector, int start, int end) product of the values in the array, from index start (inclusive) to end (exclusive)
static int	scalarProduct(int[] v1, int[] v2)
static void	secureDivide(double[] a, double[] b, double[] c) computes c := a / b , but avoids division by zero.
static void	secureSubtract(double[] a, double[] b, double[] c)
static double	sum(double[] vector)

Methods inherited from class java.lang.Object

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

Method Detail

exp

public static void exp(double[] vector)

exp

public static void exp(IArrayWrapper array)

log

public static void log(double[] vector)

log

public static void log(IArrayWrapper vector)

normalize

public static double[] normalize(double[] vector)

sum

public static double sum(double[] vector)

secureDivide

public static void secureDivide(double[] a,
                                double[] b,
                                double[] c)

computes c := a / b , but avoids division by zero. In the context of the JTA, this is valid because it holds that b == 0 -> a == 0

Parameters:

a -

b -

c -

secureSubtract

public static void secureSubtract(double[] a,
                                  double[] b,
                                  double[] c)

normalizeLog

public static double[] normalizeLog(double[] vector)

product

public static int product(int[] vector)

productOfRange

public static int productOfRange(int[] vector,
                                 int start,
                                 int end)

product of the values in the array, from index start (inclusive) to end (exclusive)

Throws:

java.lang.ArrayIndexOutOfBoundsException - if end >= vector.length

scalarProduct

public static int scalarProduct(int[] v1,
                                int[] v2)