Option Strict On

Imports System

Imports System.Collections.Generic

Imports System.Linq

Imports System.Console

Imports XorShifts

​

'XorShift Module

'Imports System.Collections.Generic

'Imports System.Linq

Namespace XorShifts

    Class XorShift

        Private r As IEnumerator(Of UInteger)

        Public Shared ReadOnly defaults As New Dictionary(Of String,UInteger) From {

            {"x",123456789},

            {"y",362436069},

            {"z",521288629},

            {"w",88675123}

        }

        Public ReadOnly seeds As Dictionary(Of String,UInteger)

        Public randCount As UInteger=0

​

        Sub New(

            Optional _w As UInteger?=Nothing,

            Optional _x As UInteger?=Nothing,

            Optional _y As UInteger?=Nothing,

            Optional _z As UInteger?=Nothing

        )

            Dim w=CUInt(If(_w IsNot Nothing,_w,CUInt(Environment.TickCount)))

            Dim x=CUInt(If(_x IsNot Nothing,_x,w<<13))

            Dim y=CUInt(If(_y IsNot Nothing,_y,w>>9 Xor x<<6))

            Dim z=CUInt(If(_z IsNot Nothing,_z,y>>7))

            seeds=New Dictionary(Of String,UInteger) From {

                {"x",x},{"y",y},{"z",z},{"w",w}

            }

            r=randGen(w,x,y,z)

        End Sub

​

        Public Iterator Function randGen(w As UInteger,x As UInteger,y As UInteger,z As UInteger) As IEnumerator(Of UInteger)

            Dim t As UInteger

            Do

                t=x Xor (x<<11)

                x=y

                y=z

                z=w

                w=(w Xor (w>>19)) Xor (t Xor (t>>8))

                Yield w

            Loop

        End Function

​

        Public Function rand() As UInteger

            randCount+=1UI

            r.MoveNext()

            Return r.Current

        End Function

​

        Public Function randInt(Optional min As Integer=0,Optional max As Integer=&H7FFFFFFFI) As Integer

            Return CInt(rand() mod (CUInt(max)-min+1)+min)

        End Function

​

        Public Function randFloat(Optional min As Single=0,Optional max As Single=1) As Single

            Return CSng((rand() mod &HFFFFUI)/&HFFFFUI*(max-min)+min)

        End Function

​

        Public Function shuffle(Of T)(_arr As T()) As T()

            Dim arr=CType(_arr.Clone(),T())

            For i=0 To arr.Length-2

                Dim r As Integer=randInt(i,arr.Length-1)

                Dim tmp As T=arr(i)

                arr(i)=arr(r)

                arr(r)=tmp

            Next

            Return arr

        End Function

​

        Public Function shuffle(Of T)(_arr As List(Of T)) As List(Of T)

            Dim arr As New List(Of T)(_arr)

            For i=0 To arr.Count-2

                Dim r As Integer=randInt(i,arr.Count-1)

                Dim tmp As T=arr(i)

                arr(i)=arr(r)

                arr(r)=tmp

            Next

            Return arr

        End Function

​

        PubLic Class defaultSeed

            Inherits XorShift

            Sub New()

                MyBase.New(

                defaults("w"),

                defaults("x"),

                defaults("y"),

                defaults("z")

                )

            End Sub

        End Class

    End Class

End Namespace

'XorShift End

​

Public Class TestXS

    Shared Sub Main()

        'XorShift乱数ジェネレータの初期化

        ' 論文デフォルトシード

        Dim r_def As New XorShift.defaultSeed()

        ' 固定値シード

        Dim r_const As New XorShift(100)

        ' 時間シード

        Dim r As New XorShift()

​

        'デフォルトシード値の取得

        WriteLine(">> defaults")

        For Each i In XorShift.defaults.Keys

            WriteLine("{0}:{1}",i,XorShift.defaults(i))

        Next

​

        '適用したシード値の取得

        WriteLine(">> seeds in r")

        For Each i In r.seeds.Keys

            WriteLine("{0}:{1}",i,XorShift.defaults(i))

        Next

​

        '乱数の生データを取得

        WriteLine(">> rand 0 to UInt32Max")

        For i=0 To 5-1

            WriteLine(r_def.rand())

        Next

​

        '0-100の乱数(100含む)を整数で取得

        WriteLine(">> randInt 0 to 100")

        For i=0 To 5-1

            WriteLine(r_const.randInt(0,100))

        Next

​

        '0-1の乱数を浮遊小数点で取得

        WriteLine(">> randFloat 0 to 1")

        For i=0 To 5-1

            WriteLine(r.randFloat())

        Next

​

        '静的配列のシャッフル

        '値渡しとなるので元の配列は破壊されない

        WriteLine(">> shuffle Array")

        Dim a As Integer()=Enumerable.Range(0,20).ToArray()

        WriteLine(String.Join(", ",r.shuffle(a)))

        WriteLine(String.Join(", ",a))

​

        'List(Of T)のシャッフル

        WriteLine(">> shuffle List(Of T)")

        Dim b As New List(Of Integer)(Enumerable.Range(0,20))

        WriteLine(String.Join(", ",r.shuffle(b)))

        WriteLine(String.Join(", ",b))

​

        '今の乱数を回した回数

        WriteLine(">> randCount in r")

        WriteLine(r.randCount)

    End Sub

End Class

​