public class MersenneTwister extends BitsStreamGenerator implements Serializable
This generator features an extremely long period (219937-1) and 623-dimensional equidistribution up to 32 bits accuracy. The home page for this generator is located at http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/emt.html.
This generator is described in a paper by Makoto Matsumoto and Takuji Nishimura in 1998: Mersenne Twister: A 623-Dimensionally Equidistributed Uniform Pseudo-Random Number Generator, ACM Transactions on Modeling and Computer Simulation, Vol. 8, No. 1, January 1998, pp 3--30
This class is mainly a Java port of the 2002-01-26 version of the generator written in C by Makoto Matsumoto and Takuji Nishimura. Here is their original copyright:
Copyright (C) 1997 - 2002, Makoto Matsumoto and Takuji Nishimura, All rights reserved. |
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
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THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
Constructor and Description |
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MersenneTwister()
Creates a new random number generator.
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MersenneTwister(int seed)
Creates a new random number generator using a single int seed.
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MersenneTwister(int[] seed)
Creates a new random number generator using an int array seed.
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MersenneTwister(long seed)
Creates a new random number generator using a single long seed.
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Modifier and Type | Method and Description |
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protected int |
next(int bits)
Generate next pseudorandom number.
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void |
setSeed(int seed)
Reinitialize the generator as if just built with the given int seed.
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void |
setSeed(int[] seed)
Reinitialize the generator as if just built with the given int array seed.
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void |
setSeed(long seed)
Reinitialize the generator as if just built with the given long seed.
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clear, nextBoolean, nextBytes, nextBytes, nextDouble, nextFloat, nextGaussian, nextInt, nextInt, nextLong, nextLong
public MersenneTwister()
The instance is initialized using the current time plus the system identity hash code of this instance as the seed.
public MersenneTwister(int seed)
seed
- the initial seed (32 bits integer)public MersenneTwister(int[] seed)
seed
- the initial seed (32 bits integers array), if null
the seed of the generator will be related to the current timepublic MersenneTwister(long seed)
seed
- the initial seed (64 bits integer)public void setSeed(int seed)
The state of the generator is exactly the same as a new generator built with the same seed.
setSeed
in interface RandomGenerator
setSeed
in class BitsStreamGenerator
seed
- the initial seed (32 bits integer)public void setSeed(int[] seed)
The state of the generator is exactly the same as a new generator built with the same seed.
setSeed
in interface RandomGenerator
setSeed
in class BitsStreamGenerator
seed
- the initial seed (32 bits integers array), if null
the seed of the generator will be the current system time plus the
system identity hash code of this instancepublic void setSeed(long seed)
The state of the generator is exactly the same as a new generator built with the same seed.
setSeed
in interface RandomGenerator
setSeed
in class BitsStreamGenerator
seed
- the initial seed (64 bits integer)protected int next(int bits)
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()
,
next(int)
and BitsStreamGenerator.nextLong()
.
next
in class BitsStreamGenerator
bits
- number of random bits to produceCopyright © 2003–2016 The Apache Software Foundation. All rights reserved.