NAME
    Math::Random::MT - The Mersenne Twister PRNG

SYNOPSIS
      ## Object-oriented interface:
      use Math::Random::MT;
      $gen = Math::Random::MT->new()        # or...
      $gen = Math::Random::MT->new($seed);  # or...
      $gen = Math::Random::MT->new(@seeds);
      $seed = $gen->get_seed();             # seed used to generate the random numbers
      $rand = $gen->rand(42);               # random number in the interval [0, 42)
      $dice = int($gen->rand(6)+1);         # random integer between 1 and 6
      $coin = $gen->rand() < 0.5 ?          # flip a coin
        "heads" : "tails"
      $int = $gen->irand();                 # random integer in [0, 2^32-1]

      ## Function-oriented interface:
      use Math::Random::MT qw(srand rand irand);
      # now use srand() and rand() as you usually do in Perl

DESCRIPTION
    The Mersenne Twister is a pseudorandom number generator developed by
    Makoto Matsumoto and Takuji Nishimura. It is described in their paper at
    <URL:http://www.math.keio.ac.jp/~nisimura/random/doc/mt.ps>. This
    algorithm has a very uniform distribution and is good for modelling
    purposes but do not use it for cryptography.

    This module implements two interfaces:

  Object-oriented interface
    new()
        Creates a new generator that is automatically seeded based on
        gettimeofday.

    new($seed)
        Creates a new generator seeded with an unsigned 32-bit integer.

    new(@seeds)
        Creates a new generator seeded with an array of (up to 624) unsigned
        32-bit integers.

    set_seed()
        Seeds the generator. It takes the same arguments as *new()*.

    get_seed()
        Retrieves the value of the seed used.

    rand($num)
        Behaves exactly like Perl's builtin rand(), returning a number
        uniformly distributed in [0, $num) ($num defaults to 1).

    irand()
        Returns a 32-bit integer, i.e. an integer uniformly distributed in
        [0, 2^32-1].

  Function-oriented interface
    srand($seed)
        Behaves just like Perl's builtin srand(). As in Perl >= 5.14, the
        seed is returned. If you use this interface, it is strongly
        recommended that you call *srand()* explicitly, rather than relying
        on *rand()* to call it the first time it is used.

    rand($num)
        Behaves exactly like Perl's builtin rand(), returning a number
        uniformly distributed in [0, $num) ($num defaults to 1).

    irand()
        Returns a 32-bit integer, i.e. an integer uniformly distributed in
        [0, 2^32-1].

SEE ALSO
    <URL:http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/emt.html>

    Data::Entropy

ACKNOWLEDGEMENTS
    Sean M. Burke
        For giving me the idea to write this module.

    Philip Newton
        For several useful patches.

    Florent Angly
        For implementing seed generation and retrieval.

AUTHOR
    Abhijit Menon-Sen <ams@toroid.org>

    Copyright 2001 Abhijit Menon-Sen. All rights reserved.

    Based on the C implementation of MT19937 Copyright (C) 1997 - 2002,
    Makoto Matsumoto and Takuji Nishimura

    This software is distributed under a (three-clause) BSD-style license.
    See the LICENSE file in the distribution for details.