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 Description

MathTools()

Method Summary

Modifier and Type	Method	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).