umontreal.iro.lecuyer.randvar
Class ErlangConvolutionGen

java.lang.Object
  umontreal.iro.lecuyer.randvar.RandomVariateGen
      umontreal.iro.lecuyer.randvar.GammaGen
          umontreal.iro.lecuyer.randvar.ErlangGen
              umontreal.iro.lecuyer.randvar.ErlangConvolutionGen

public class ErlangConvolutionGen
extends ErlangGen

This class implements Erlang random variate generators using the convolution method. This method uses inversion to generate k exponential variates with parameter λ and returns their sum.

Constructor Summary

ErlangConvolutionGen(RandomStream s, ErlangDist dist)
Creates a new generator for the distribution dist and stream s.

ErlangConvolutionGen(RandomStream s, int k)
Creates an Erlang random variate generator with parameters k and λ = 1, using stream s.

ErlangConvolutionGen(RandomStream s, int k, double lambda)
Creates an Erlang random variate generator with parameters k and λ = lambda, using stream s.

Method Summary

double	nextDouble() Generates a random number from the continuous distribution contained in this object.
static double	nextDouble(RandomStream s, int k, double lambda)

Methods inherited from class umontreal.iro.lecuyer.randvar.ErlangGen

getK

Methods inherited from class umontreal.iro.lecuyer.randvar.GammaGen

getAlpha, getLambda, nextDouble

Methods inherited from class umontreal.iro.lecuyer.randvar.RandomVariateGen

getDistribution, getStream, nextArrayOfDouble, setStream, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

ErlangConvolutionGen

public ErlangConvolutionGen(RandomStream s,
                            int k,
                            double lambda)

Creates an Erlang random variate generator with parameters k and λ = lambda, using stream s.

ErlangConvolutionGen

public ErlangConvolutionGen(RandomStream s,
                            int k)

Creates an Erlang random variate generator with parameters k and λ = 1, using stream s.

ErlangConvolutionGen

public ErlangConvolutionGen(RandomStream s,
                            ErlangDist dist)

Creates a new generator for the distribution dist and stream s.

Method Detail

nextDouble

public double nextDouble()

Description copied from class: RandomVariateGen

Generates a random number from the continuous distribution contained in this object. By default, this method uses inversion by calling the inverseF method of the distribution object. Alternative generating methods are provided in subclasses.

Overrides:

nextDouble in class RandomVariateGen

Returns:

the generated value

nextDouble

public static double nextDouble(RandomStream s,
                                int k,
                                double lambda)