umontreal.iro.lecuyer.randvar

Class HalfNormalGen

java.lang.Object

umontreal.iro.lecuyer.randvar.RandomVariateGen

umontreal.iro.lecuyer.randvar.HalfNormalGen

public class HalfNormalGen
extends RandomVariateGen

This class implements methods for generating random variates from the half-normal distribution with parameters μ and σ > 0. Its density is

f (x) = ((2/π)^1/2/σ)e^{-(x-μ)2/(2σ2)}, for x > = μ,

Constructor Summary

Constructors

Constructor and Description
HalfNormalGen(RandomStream s, double mu, double sigma) Creates a new half-normal generator with parameters μ = mu and σ = sigma, using stream s.
HalfNormalGen(RandomStream s, HalfNormalDist dist) Creates a new generator for the distribution dist, using stream s.

Method Summary

Modifier and Type	Method and Description
double	getMu() Returns the parameter μ of this object.
double	getSigma() Returns the parameter σ of this object.
static double	nextDouble(RandomStream s, double mu, double sigma) Generates a variate from the half-normal distribution with parameters μ = mu and σ = sigma, using stream s.

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

getDistribution, getStream, nextArrayOfDouble, nextDouble, setStream, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

HalfNormalGen

public HalfNormalGen(RandomStream s,
                     double mu,
                     double sigma)

Creates a new half-normal generator with parameters μ = mu and σ = sigma, using stream s.

HalfNormalGen

public HalfNormalGen(RandomStream s,
                     HalfNormalDist dist)

Creates a new generator for the distribution dist, using stream s.

Method Detail

nextDouble

public static double nextDouble(RandomStream s,
                                double mu,
                                double sigma)

Generates a variate from the half-normal distribution with parameters μ = mu and σ = sigma, using stream s.

Parameters:

s - the random stream

mu - the parameter mu

sigma - the parameter sigma

Returns:

Generates a variate from the HalfNormal distribution

getMu

public double getMu()

Returns the parameter μ of this object.

Returns:

the parameter mu

getSigma

public double getSigma()

Returns the parameter σ of this object.

Returns:

the parameter mu