Vim documentation: vital/Random/Mt19937ar

vital/Random/Mt19937ar.txt    random number generator using mt19937ar

Maintainer: Linda_pp  <lin90162@gmail.com>

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CONTENTS                                        Vital.Random.Mt19937ar-contents

INTRODUCTION                    Vital.Random.Mt19937ar-introduction
INTERFACE                       Vital.Random.Mt19937ar-interface
  FUNCTIONS                     Vital.Random.Mt19937ar-functions



==============================================================================
INTRODUCTION                            Vital.Random.Mt19937ar-introduction

Vital.Random.Mt19937ar provides a Random Number Generator (RNG) using Mersenne
Twister algorithm.  Random numbers generated by mt19937ar have very long period
and high order of equidistribution.

http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/emt.html

The algorithm was ported to Vim script by Yukihiro Nakadaira and this module is
imported from the implementation.

https://github.com/ynkdir/vim-funlib/blob/master/autoload/random/mt19937ar.vim

This implementation always generates 32bit number [-2147483648, 2147483647],
even when you use Vim with +num64.


        let s:V = vital#{plugin-name}#new()
        let s:M = s:V.import("Random.Mt19937ar")

        call s:M.srand(1)
        echo s:M.rand()
        " 1067595299
        echo s:M.rand()
        " 955945823
        call s:M.srand(1)
        echo s:M.rand()
        " 1067595299



==============================================================================
INTERFACE                               Vital.Random.Mt19937ar-interface

------------------------------------------------------------------------------
FUNCTIONS                               Vital.Random.Mt19937ar-functions

srand([{seed}])                         Vital.Random.Mt19937ar.srand()
        Set a seed of generator.  When {seed} is omitted, a return value of
        reltime() is used.  When {seed} is omitted and vim doesn't have
        reltime(), a return value of localtime() is used.  The seed is a
        number.

rand()                                  Vital.Random.Mt19937ar.rand()
        Generate a random number.
        Note: A return value is possibly negative.  This is because Vim script
        doesn't have an unsigned integer type.

new_generator()                         Vital.Random.Mt19937ar.new_generator()
        Create a new Generator object(Vital.Random.Mt19937ar-Generator).



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OBJECTS                                 Vital.Random.Mt19937ar-objects

------------------------------------------------------------------------------
Generator Object                Vital.Random.Mt19937ar-Generator

Generator.next()                Vital.Random.Mt19937ar-Generator.next()
        Get the next random number in the sequence.

Generator.min()                 Vital.Random.Mt19937ar-Generator.min()
        Get the smallest possible value in the output range.

Generator.max()                 Vital.Random.Mt19937ar-Generator.max()
        Get the largest possible value in the output range.

Generator.seed({seeds})         Vital.Random.Mt19937ar-Generator.seed()
        Set seeds by array of numbers which initializes the generator.  The
        size of the array is arbitrary.


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vim:tw=78:fo=tcq2mM:ts=8:ft=help:norl