net.sf.tweety.commons.util

Class MathTools

java.lang.Object

net.sf.tweety.commons.util.MathTools

public class MathTools
extends java.lang.Object

This class contains some useful math tools.

Author:

Matthias Thimm

Constructor Summary

Constructors

Constructor and Description
MathTools()

Method Summary

Modifier and Type	Method and Description
static Pair<java.lang.Double,java.lang.Double>	averageAndVariance(java.util.Collection<java.lang.Double> values) Compute the average value and the variance of the given list of numbers.
static java.lang.Integer	binomial(java.lang.Integer n, java.lang.Integer k) This method computes "n choose k".
static int	faculty(int i) Computes the faculty of the given number.

Methods inherited from class java.lang.Object

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

Constructor Detail

MathTools

public MathTools()

Method Detail

binomial

public static java.lang.Integer binomial(java.lang.Integer n,
                                         java.lang.Integer k)

This method computes "n choose k". If n < 0 or k < 0 the result is defined to be 0.

Parameters:

n - an integer.

k - an integer

Returns:

the value of "n choose k".

faculty

public static int faculty(int i)

Computes the faculty of the given number.

Parameters:

i - an integer.

Returns:

the value 1*...*i or 1 if i==0.

averageAndVariance

public static Pair<java.lang.Double,java.lang.Double> averageAndVariance(java.util.Collection<java.lang.Double> values)

Compute the average value and the variance of the given list of numbers.

Parameters:

values - some values

Returns:

a pair of average value (first element) and variance (second element).