Class AbstractWell

java.lang.Object

org.apache.commons.rng.core.BaseProvider

org.apache.commons.rng.core.source32.IntProvider

org.apache.commons.rng.core.source32.AbstractWell

All Implemented Interfaces:

RandomIntSource, RestorableUniformRandomProvider, UniformRandomProvider

Direct Known Subclasses:

Well1024a, Well19937a, Well44497a, Well512a

public abstract class AbstractWell
extends IntProvider

This abstract class implements the WELL class of 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:

1.0

See Also:

• WELL Random number generator

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
protected static final class	AbstractWell.IndexTable	Inner class used to store the indirection index table which is fixed for a given type of WELL class of pseudo-random number generator.

Field Summary

Fields

Modifier and Type	Field	Description
protected int	index	Current index in the bytes pool.
protected final int[]	v	Bytes pool.

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	AbstractWell(int k, int[] seed)	Creates an instance with the given seed.

Method Summary

Modifier and Type	Method	Description
protected byte[]	getStateInternal()	Creates a snapshot of the RNG state.
protected void	setStateInternal(byte[] s)	Resets the RNG to the given state.

Methods inherited from class IntProvider

nextBoolean, nextBytes, nextBytes, nextDouble, nextInt, nextLong, resetCachedState

Methods inherited from class BaseProvider

checkIndex, checkStateSize, composeStateInternal, extendSeed, extendSeed, fillState, fillState, restoreState, saveState, splitStateInternal, toString

Methods inherited from class Object

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

Methods inherited from interface RandomIntSource

next

Methods inherited from interface UniformRandomProvider

doubles, doubles, doubles, doubles, ints, ints, ints, ints, longs, longs, longs, longs, nextDouble, nextDouble, nextFloat, nextFloat, nextFloat, nextInt, nextInt, nextLong, nextLong

Field Details

index

protected int index

Current index in the bytes pool.

v

protected final int[] v

Bytes pool.

Constructor Details

AbstractWell

protected AbstractWell(int k,
 int[] seed)

Creates an instance with the given seed.

Parameters:

k - Number of bits in the pool (not necessarily a multiple of 32).

seed - Initial seed.

Method Details

getStateInternal

protected byte[] getStateInternal()

Creates a snapshot of the RNG state.

Overrides:

getStateInternal in class IntProvider

Returns:

the internal state.

setStateInternal

protected void setStateInternal(byte[] s)

Resets the RNG to the given state.

Overrides:

setStateInternal in class IntProvider

Parameters:

s - State (previously obtained by a call to BaseProvider.getStateInternal()).

See Also:

• BaseProvider.checkStateSize(byte[],int)