Package org.apache.commons.math.random

Class MersenneTwister

  • All Implemented Interfaces:
    java.io.Serializable, RandomGenerator
    public class MersenneTwister
extends BitsStreamGenerator
implements java.io.Serializable
    This class implements a powerful pseudo-random number generator developed by Makoto Matsumoto and Takuji Nishimura during 1996-1997.

    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:
    1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
    2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
    3. The names of its contributors may not be used to endorse or promote products derived from this software without specific prior written permission.
    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.
    Since:
    2.0
    Version:
    $Revision: 990655 $ $Date: 2010-08-29 23:49:40 +0200 (dim. 29 août 2010) $
    See Also:
    Serialized Form

    • Constructor Summary

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

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      protected int next​(int bits)
      Generate next pseudorandom number.
      void setSeed​(int seed)
      Reinitialize the generator as if just built with the given int seed.
      void setSeed​(int[] seed)
      Reinitialize the generator as if just built with the given int array seed.
      void setSeed​(long seed)
      Reinitialize the generator as if just built with the given long seed.

      • Methods inherited from class java.lang.Object

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

    • Constructor Detail

      • MersenneTwister

        public MersenneTwister()
        Creates a new random number generator.

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

      • MersenneTwister

        public MersenneTwister​(int seed)
        Creates a new random number generator using a single int seed.
        Parameters:
        seed - the initial seed (32 bits integer)

      • MersenneTwister

        public MersenneTwister​(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

      • MersenneTwister

        public MersenneTwister​(long seed)
        Creates a new random number generator using a single long seed.
        Parameters:
        seed - the initial seed (64 bits integer)