Class Well512a

java.lang.Object

org.apache.commons.math3.random.BitsStreamGenerator

org.apache.commons.math3.random.AbstractWell

org.apache.commons.math3.random.Well512a

All Implemented Interfaces:

Serializable, RandomGenerator

public class Well512a
extends AbstractWell

This class implements the WELL512a 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	Description
private static final int	K	Number of bits in the pool.
private static final int	M1	First parameter of the algorithm.
private static final int	M2	Second parameter of the algorithm.
private static final int	M3	Third parameter of the algorithm.
private static final long	serialVersionUID	Serializable version identifier.

Fields inherited from class AbstractWell

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

Constructor Summary

Constructors

Constructor	Description
Well512a()	Creates a new random number generator.
Well512a(int seed)	Creates a new random number generator using a single int seed.
Well512a(int[] seed)	Creates a new random number generator using an int array seed.
Well512a(long seed)	Creates a new random number generator using a single long seed.

Method Summary

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

Methods inherited from class AbstractWell

setSeed, setSeed, setSeed

Methods inherited from class BitsStreamGenerator

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

Methods inherited from class Object

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

Field Details

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 Details

Well512a

public Well512a()

Creates a new random number generator.

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

Well512a

public Well512a(int seed)

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

Parameters:

seed - the initial seed (32 bits integer)

Well512a

public Well512a(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

Well512a

public Well512a(long seed)

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

Parameters:

seed - the initial seed (64 bits integer)

Method Details

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