java.lang.Object
- adams.data.random.Random

All Implemented Interfaces:

Serializable
```
public class Random
extends Object
implements Serializable
```
Based on JMathArray's org.math.array.util.Random class. But in comparison to the original class, this one here is seedable and all methods are non-static.

Version:

$Revision$

Author:

Yann RICHET (original JMathArray code), fracpete (fracpete at waikato dot ac dot nz)

See Also:

Serialized Form

Nested Class Summary

Nested Classes
Modifier and Type Class Description

static interface Random.Function
Based on JMathArray's org.math.array.util.Function.

Field Summary

Fields
Modifier and Type Field Description

protected RandomSeedable m_RandEngine
the random number generator.

Constructor Summary

Constructors
Constructor	Description
`Random()`	Initializes the random number generator with a default (but fixed) seed value.
`Random(long seed)`	Initializes the random number generator with the specified seed value.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`double`	`beta(double a, double b)`	Generate a random number from a beta random variable.
`double`	`cauchy(double mu, double sigma)`	Generate a random number from a Cauchy random variable (Mean = Inf, and Variance = Inf).
`double`	`chi2(int n)`	Generate a random number from a Chi-2 random variable.
`double`	`dirac(double[] values, double[] prob)`	Generate a random number from a discrete random variable.
`double`	`exponential(double lambda)`	Generate a random number from an exponantial random variable (Mean = 1/lambda, variance = 1/lambda^2).
`double`	`logNormal(double mu, double sigma)`	Generate a random number from a LogNormal random variable.
`double`	`normal(double mu, double sigma)`	Generate a random number from a Gaussian (Normal) random variable.
`int`	`randInt(int i0, int i1)`	Generate a random integer.
`double`	`raw()`	Generate a random number between 0 and 1.
`double`	`rejection(Random.Function fun, double maxFun, double min, double max)`	Generate a random number from a random variable definied by its density function, using the rejection technic.
`double`	`triangular(double min, double max)`	Generate a random number from a symetric triangular random variable.
`double`	`triangular(double min, double med, double max)`	Generate a random number from a non-symetric triangular random variable.
`double`	`uniform(double min, double max)`	Generate a random number from a uniform random variable.
`double`	`weibull(double lambda, double c)`	Generate a random number from a Weibull random variable.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - m_RandEngine
```
protected RandomSeedable m_RandEngine
```
    the random number generator.
- Constructor Detail
  - Random
```
public Random()
```
    Initializes the random number generator with a default (but fixed) seed value.
  - Random
```
public Random(long seed)
```
    Initializes the random number generator with the specified seed value.
    
    Parameters:
    
    seed - the seed value to use
- Method Detail
  - raw
```
public double raw()
```
    Generate a random number between 0 and 1. maybe changed for a better random number generator if needed.
    
    Returns:
    
    A double between 0 and 1.
  - randInt
```
public int randInt(int i0,
                   int i1)
```
    Generate a random integer.
    
    Parameters:
    
    i0 - Min of the random variable.
    
    i1 - Max of the random variable.
    
    Returns:
    
    An int between i0 and i1.
  - uniform
```
public double uniform(double min,
                      double max)
```
    Generate a random number from a uniform random variable.
    
    Parameters:
    
    min - Min of the random variable.
    
    max - Max of the random variable.
    
    Returns:
    
    A double.
  - dirac
```
public double dirac(double[] values,
                    double[] prob)
```
    Generate a random number from a discrete random variable.
    
    Parameters:
    
    values - Discrete values.
    
    prob - Probability of each value.
    
    Returns:
    
    A double.
  - normal
```
public double normal(double mu,
                     double sigma)
```
    Generate a random number from a Gaussian (Normal) random variable.
    
    Parameters:
    
    mu - Mean of the random variable.
    
    sigma - Standard deviation of the random variable.
    
    Returns:
    
    A double.
  - chi2
```
public double chi2(int n)
```
    Generate a random number from a Chi-2 random variable.
    
    Parameters:
    
    n - Degrees of freedom of the chi2 random variable.
    
    Returns:
    
    A double.
  - logNormal
```
public double logNormal(double mu,
                        double sigma)
```
    Generate a random number from a LogNormal random variable.
    
    Parameters:
    
    mu - Mean of the Normal random variable.
    
    sigma - Standard deviation of the Normal random variable.
    
    Returns:
    
    A double.
  - exponential
```
public double exponential(double lambda)
```
    Generate a random number from an exponantial random variable (Mean = 1/lambda, variance = 1/lambda^2).
    
    Parameters:
    
    lambda - Parmaeter of the exponential random variable.
    
    Returns:
    
    A double.
  - triangular
```
public double triangular(double min,
                         double max)
```
    Generate a random number from a symetric triangular random variable.
    
    Parameters:
    
    min - Min of the random variable.
    
    max - Max of the random variable.
    
    Returns:
    
    A double.
  - triangular
```
public double triangular(double min,
                         double med,
                         double max)
```
    Generate a random number from a non-symetric triangular random variable.
    
    Parameters:
    
    min - Min of the random variable.
    
    med - Value of the random variable with max density.
    
    max - Max of the random variable.
    
    Returns:
    
    A double.
  - beta
```
public double beta(double a,
                   double b)
```
    Generate a random number from a beta random variable.
    
    Parameters:
    
    a - First parameter of the Beta random variable.
    
    b - Second parameter of the Beta random variable.
    
    Returns:
    
    A double.
  - cauchy
```
public double cauchy(double mu,
                     double sigma)
```
    Generate a random number from a Cauchy random variable (Mean = Inf, and Variance = Inf).
    
    Parameters:
    
    mu - Median of the Weibull random variable
    
    sigma - Second parameter of the Cauchy random variable.
    
    Returns:
    
    A double.
  - weibull
```
public double weibull(double lambda,
                      double c)
```
    Generate a random number from a Weibull random variable.
    
    Parameters:
    
    lambda - First parameter of the Weibull random variable.
    
    c - Second parameter of the Weibull random variable.
    
    Returns:
    
    A double.
  - rejection
```
public double rejection(Random.Function fun,
                        double maxFun,
                        double min,
                        double max)
```
    Generate a random number from a random variable definied by its density function, using the rejection technic. !!! WARNING : this simulation technic can take a very long time !!!
    
    Parameters:
    
    fun - Density function (may be not normalized) of the random variable.
    
    maxFun - Max of the function.
    
    min - Min of the random variable.
    
    max - Max of the random variable.
    
    Returns:
    
    A double.

Class Random

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

m_RandEngine

Constructor Detail

Random

Random

Method Detail

raw

randInt

uniform

dirac

normal

chi2

logNormal

exponential

triangular

triangular

beta

cauchy

weibull

rejection