org.apache.commons.math3.random

Class Well19937c

java.lang.Object

org.apache.commons.math3.random.BitsStreamGenerator

org.apache.commons.math3.random.AbstractWell

org.apache.commons.math3.random.Well19937c

All Implemented Interfaces:

java.io.Serializable, RandomGenerator

public class Well19937c
extends AbstractWell

This class implements the WELL19937c pseudo-random number generator from François Panneton, Pierre L'Ecuyer and Makoto Matsumoto.

This generator is described in a paper by François Panneton, Pierre L'Ecuyer and Makoto Matsumoto Improved Long-Period Generators Based on Linear Recurrences Modulo 2 ACM Transactions on Mathematical Software, 32, 1 (2006). The errata for the paper are in wellrng-errata.txt.

Since:

2.2

See Also:

WELL Random number generator, Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
private static int	K Number of bits in the pool.
private static int	M1 First parameter of the algorithm.
private static int	M2 Second parameter of the algorithm.
private static int	M3 Third parameter of the algorithm.
private static long	serialVersionUID Serializable version identifier.

Fields inherited from class org.apache.commons.math3.random.AbstractWell

i1, i2, i3, index, iRm1, iRm2, v

Constructor Summary

Constructors

Constructor and Description
Well19937c() Creates a new random number generator.
Well19937c(int seed) Creates a new random number generator using a single int seed.
Well19937c(int[] seed) Creates a new random number generator using an int array seed.
Well19937c(long seed) Creates a new random number generator using a single long seed.

Method Summary

Methods

Modifier and Type	Method and Description
protected int	next(int bits) Generate next pseudorandom number.

Methods inherited from class org.apache.commons.math3.random.AbstractWell

setSeed, setSeed, setSeed

Methods inherited from class org.apache.commons.math3.random.BitsStreamGenerator

clear, nextBoolean, nextBytes, nextBytes, nextDouble, nextFloat, nextGaussian, nextInt, nextInt, nextLong, nextLong

Methods inherited from class java.lang.Object

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

Field Detail

serialVersionUID

private static final long serialVersionUID

Serializable version identifier.

See Also:

Constant Field Values

K

private static final int K

Number of bits in the pool.

See Also:

Constant Field Values

M1

private static final int M1

First parameter of the algorithm.

See Also:

Constant Field Values

M2

private static final int M2

Second parameter of the algorithm.

See Also:

Constant Field Values

M3

private static final int M3

Third parameter of the algorithm.

See Also:

Constant Field Values

Constructor Detail

Well19937c

public Well19937c()

Creates a new random number generator.

The instance is initialized using the current time as the seed.

Well19937c

public Well19937c(int seed)

Creates a new random number generator using a single int seed.

Parameters:

seed - the initial seed (32 bits integer)

Well19937c

public Well19937c(int[] seed)

Creates a new random number generator using an int array seed.

Parameters:

seed - the initial seed (32 bits integers array), if null the seed of the generator will be related to the current time

Well19937c

public Well19937c(long seed)

Creates a new random number generator using a single long seed.

Parameters:

seed - the initial seed (64 bits integer)

Method Detail

next

protected int next(int bits)

Generate next pseudorandom number.

This method is the core generation algorithm. It is used by all the public generation methods for the various primitive types BitsStreamGenerator.nextBoolean(), BitsStreamGenerator.nextBytes(byte[]), BitsStreamGenerator.nextDouble(), BitsStreamGenerator.nextFloat(), BitsStreamGenerator.nextGaussian(), BitsStreamGenerator.nextInt(), BitsStreamGenerator.next(int) and BitsStreamGenerator.nextLong().

Specified by:

next in class AbstractWell

Parameters:

bits - number of random bits to produce

Returns:

random bits generated