umontreal.iro.lecuyer.rng

Class GenF2w32

java.lang.Object

umontreal.iro.lecuyer.rng.RandomStreamBase

umontreal.iro.lecuyer.rng.GenF2w32

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable, CloneableRandomStream, RandomStream

public class GenF2w32
extends RandomStreamBase

Implements the RandomStream interface via inheritance from RandomStreamBase. The backbone generator is a Linear Congruential Generator (LCG) in the finite field F_2^w instead of F₂. The implemented generator is the GenF2w2_32 proposed by Panneton. Its state is 25 32-bit words and it has a period length of 2⁸⁰⁰ - 1. The values of V, W and Z are 2²⁰⁰, 2³⁰⁰ and 2⁵⁰⁰ respectively (see RandomStream for their definition). The seed of the RNG, and the state of a stream at any given step, is a 25-dimensional vector of 32-bits integers. Its nextValue method returns numbers with 32 bits of precision.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
GenF2w32() Constructs a new stream.
GenF2w32(java.lang.String name) Constructs a new stream with the identifier name (used in the toString method).

Method Summary

Methods

Modifier and Type	Method and Description
GenF2w32	clone() Clones the current generator and return its copy.
int[]	getState() Returns the current state of the stream, represented as an array of 25 integers.
static void	main(java.lang.String[] args) This method is only meant to be used during the compilation process.
void	resetNextSubstream() Reinitializes the stream to the beginning of its next substream: Ng is computed, and Cg and Bg are set to Ng.
void	resetStartStream() Reinitializes the stream to its initial state Ig: Cg and Bg are set to Ig.
void	resetStartSubstream() Reinitializes the stream to the beginning of its current substream: Cg is set to Bg.
static void	setPackageSeed(int[] seed) Sets the initial seed of the class GenF2w2r32 to the 25 integers of the vector seed[0..24].
void	setSeed(int[] seed) This method is discouraged for normal use.
java.lang.String	toString() Returns a string containing the current state of this stream.

Methods inherited from class umontreal.iro.lecuyer.rng.RandomStreamBase

formatState, formatStateFull, increasedPrecision, nextArrayOfDouble, nextArrayOfInt, nextDouble, nextInt

Methods inherited from class java.lang.Object

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

Constructor Detail

GenF2w32

public GenF2w32()

Constructs a new stream.

GenF2w32

public GenF2w32(java.lang.String name)

Constructs a new stream with the identifier name (used in the toString method).

Parameters:

name - name of the stream

Method Detail

setPackageSeed

public static void setPackageSeed(int[] seed)

Sets the initial seed of the class GenF2w2r32 to the 25 integers of the vector seed[0..24]. This will be the initial seed of the class for the next created stream. At least one of the integers must be non-zero.

Parameters:

seed - array of 25 elements representing the seed

setSeed

public void setSeed(int[] seed)

This method is discouraged for normal use. Initializes the stream at the beginning of a stream with the initial seed seed[0..24]. The seed must satisfy the same conditions as in setPackageSeed. This method only affects the specified stream; the others are not modified. Hence after calling this method, the beginning of the streams will no longer be spaced Z values apart. For this reason, this method should only be used in very exceptional cases; proper use of the reset... methods and of the stream constructor is preferable.

Parameters:

seed - array of 25 elements representing the seed

getState

public int[] getState()

Returns the current state of the stream, represented as an array of 25 integers.

Returns:

the current state of the stream

clone

public GenF2w32 clone()

Clones the current generator and return its copy.

Specified by:

clone in interface CloneableRandomStream

Overrides:

clone in class RandomStreamBase

Returns:

A deep copy of the current generator

resetStartStream

public void resetStartStream()

Description copied from interface: RandomStream

Reinitializes the stream to its initial state I_g: C_g and B_g are set to I_g.

Specified by:

resetStartStream in interface RandomStream

Specified by:

resetStartStream in class RandomStreamBase

resetStartSubstream

public void resetStartSubstream()

Description copied from interface: RandomStream

Reinitializes the stream to the beginning of its current substream: C_g is set to B_g.

Specified by:

resetStartSubstream in interface RandomStream

Specified by:

resetStartSubstream in class RandomStreamBase

resetNextSubstream

public void resetNextSubstream()

Description copied from interface: RandomStream

Reinitializes the stream to the beginning of its next substream: N_g is computed, and C_g and B_g are set to N_g.

Specified by:

resetNextSubstream in interface RandomStream

Specified by:

resetNextSubstream in class RandomStreamBase

toString

public java.lang.String toString()

Description copied from interface: RandomStream

Returns a string containing the current state of this stream.

Specified by:

toString in interface RandomStream

Specified by:

toString in class RandomStreamBase

Returns:

the state of the generator formated as a string

main

public static void main(java.lang.String[] args)

This method is only meant to be used during the compilation process. It is used to create the resource file the class need in order to run.