IRPact_modellierung.distributions

Class ErlangDistribution

java.lang.Object

IRPact_modellierung.distributions.Distribution

IRPact_modellierung.distributions.UnivariateDistribution

IRPact_modellierung.distributions.ContinuousDistribution

IRPact_modellierung.distributions.COLTContinuousDistribution

IRPact_modellierung.distributions.ErlangDistribution

public class ErlangDistribution
extends COLTContinuousDistribution

Class to represent an Erlang distribution based on the COLT distribution library. Because of this, the parameters are modeled as double values

Field Summary

Fields inherited from class IRPact_modellierung.distributions.COLTContinuousDistribution

generator

Fields inherited from class IRPact_modellierung.distributions.Distribution

name

Constructor Summary

Constructors

Constructor and Description
ErlangDistribution(java.lang.String name, int k, double lambda) Generate an Erlang distribution from the parameters k (shape) and lambda (rate), which is used to draw values based on the mean and variance of the distribution as implemented in the COLT library

Method Summary

Modifier and Type	Method and Description
double	draw() Draw a value from the distribution according to the distribution at hand
double	drawValue() Value is drawn using the nextErlang-function of the COLT distributions
int	k()
double	lambda()
void	setK(int k) Resets the shape parameter k of the distribution.
void	setLambda(double lambda) Resets the rate parameter lambda of the distribution.

Methods inherited from class IRPact_modellierung.distributions.Distribution

getName, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

ErlangDistribution

public ErlangDistribution(java.lang.String name,
                          int k,
                          double lambda)

Generate an Erlang distribution from the parameters k (shape) and lambda (rate), which is used to draw values based on the mean and variance of the distribution as implemented in the COLT library

Parameters:

name - The name of the distribution used (will be prefixed by ErlangDistribution_)

k - The shape parameter of the Erlang distribution

lambda - The rate parameter of the Erlang distribution

Throws:

java.lang.IllegalArgumentException - will be thrown when either parameter is out of range (<= 0)

Method Detail

k

public int k()

lambda

public double lambda()

setK

public void setK(int k)
          throws java.lang.IllegalArgumentException

Resets the shape parameter k of the distribution. Will also recalculate the parameters the COLT distribution used is based upon.

Parameters:

k - shape parameter to replace current one

Throws:

java.lang.IllegalArgumentException - Will be thrown when k <= 0

setLambda

public void setLambda(double lambda)
               throws java.lang.IllegalArgumentException

Resets the rate parameter lambda of the distribution. Will also recalculate the parameters the COLT distribution used is based upon.

Parameters:

lambda - rate parameter to replace current one

Throws:

java.lang.IllegalArgumentException - Will be thrown when lambda <= 0

drawValue

public double drawValue()

Value is drawn using the nextErlang-function of the COLT distributions

Returns:

value according to the Erlang distribution using the COLT library

draw

public double draw()

Description copied from class: UnivariateDistribution

Draw a value from the distribution according to the distribution at hand

Specified by:

draw in class UnivariateDistribution

Returns:

A double number drawn from the modeled distribution