1 | #Region "Microsoft.VisualBasic::fbb21f6b7839c9c68891c6e7a6946bb4, Microsoft.VisualBasic.Core\Extensions\Math\Random\RandomRange.vb" |
2 | |
3 | ' Author: |
4 | ' |
5 | ' asuka (amethyst.asuka@gcmodeller.org) |
6 | ' xie (genetics@smrucc.org) |
7 | ' xieguigang (xie.guigang@live.com) |
8 | ' |
9 | ' Copyright (c) 2018 GPL3 Licensed |
10 | ' |
11 | ' |
12 | ' GNU GENERAL PUBLIC LICENSE (GPL3) |
13 | ' |
14 | ' |
15 | ' This program is free software: you can redistribute it and/or modify |
16 | ' it under the terms of the GNU General Public License as published by |
17 | ' the Free Software Foundation, either version 3 of the License, or |
18 | ' (at your option) any later version. |
19 | ' |
20 | ' This program is distributed in the hope that it will be useful, |
21 | ' but WITHOUT ANY WARRANTY; without even the implied warranty of |
22 | ' MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
23 | ' GNU General Public License for more details. |
24 | ' |
25 | ' You should have received a copy of the GNU General Public License |
26 | ' along with this program. If not, see <http://www.gnu.org/licenses/>. |
27 | |
28 | |
29 | |
30 | ' /********************************************************************************/ |
31 | |
32 | ' Summaries: |
33 | |
34 | ' Module RandomRange |
35 | ' |
36 | ' Function: GetRandom, Testing |
37 | ' |
38 | ' |
39 | ' /********************************************************************************/ |
40 | |
41 | #End Region |
42 | |
43 | Imports Microsoft.VisualBasic.ComponentModel.Ranges.Model |
44 | Imports Microsoft.VisualBasic.Language |
45 | Imports Microsoft.VisualBasic.Linq |
46 | Imports sys = System.Math |
47 | |
48 | Namespace Math |
49 | |
50 | ''' <summary> |
51 | ''' 针对负数到正数的range随机数,小数位最多精确到1E-4 |
52 | ''' </summary> |
53 | Public Module RandomRange |
54 | |
55 | ''' <summary> |
56 | ''' |
57 | ''' </summary> |
58 | ''' <param name="from"></param> |
59 | ''' <param name="[to]"></param> |
60 | ''' <param name="INF"></param> |
61 | ''' <param name="forceInit"> |
62 | ''' True的时候会通过牺牲性能来强制重新实例化随机数发生器来获取足够的随机 |
63 | ''' </param> |
64 | ''' <returns></returns> |
65 | Public Function GetRandom(from#, to#, Optional INF% = 5, Optional forceInit As Boolean = False) As IValueProvider |
66 | Dim pf! = ScientificNotation.PowerLog10(from, INF), pt! = ScientificNotation.PowerLog10([to], INF) |
67 | |
68 | If from > 0 Then |
69 | If [to] > 0 Then ' from 是正数,则to也必须是正数 |
70 | If pf <> 0F Then ' 如果from不是常数(极大数或者极小数),则整体当做极值数来看待 |
71 | Return AddressOf New PreciseRandom(pf, CSng(sys.Log10([to]))).NextNumber |
72 | Else ' from 是常数 |
73 | If pt > 0 Then ' 同样的,当to也是极值数的时候,整体也将被当做极值数来看待 |
74 | Return AddressOf New PreciseRandom(CSng(sys.Log10(from)), pt).NextNumber |
75 | Else |
76 | ' to 也是常数 |
77 | Dim range As New DoubleRange(from, [to]) |
78 | |
79 | If forceInit Then |
80 | Return Function() New Random().NextDouble(range) ' 想要通过牺牲性能来强制获取足够的随机 |
81 | Else |
82 | Dim rnd As New Random |
83 | Return Function() rnd.NextDouble(range) ' 假若二者都是常数,则返回常数随机区间 |
84 | End If |
85 | End If |
86 | End If |
87 | Else |
88 | Throw New InvalidConstraintException( |
89 | $"Can not creates a range as min is positive but max is negative! (from:={from}, to:={[to]})") |
90 | End If |
91 | Else ' from是负数 |
92 | If [to] > 0 Then ' to 是正数 |
93 | If pf <> 0F OrElse pt <> 0F Then ' from是极值数,则整体当做极值数来看待 |
94 | |
95 | pf = sys.Log10(sys.Abs(from)) |
96 | pt = sys.Log10(sys.Abs([to])) |
97 | |
98 | Dim c!() = {0F, pf} |
99 | Dim rf As New PreciseRandom(c.Min, c.Max) |
100 | c = {0F, pt} |
101 | Dim rt As New PreciseRandom(c.Min, c.Max) |
102 | Dim ppf = sys.Abs(pf) / (sys.Abs(pf) + sys.Abs(pt)) |
103 | |
104 | If forceInit Then |
105 | Return Function() |
106 | If New Random().NextDouble < ppf Then |
107 | Return -1 * rf.NextNumber |
108 | Else |
109 | Return rt.NextNumber |
110 | End If |
111 | End Function |
112 | Else |
113 | Dim rnd As New Random |
114 | Return Function() |
115 | If rnd.NextDouble < ppf Then |
116 | Return -1 * rf.NextNumber |
117 | Else |
118 | Return rt.NextNumber |
119 | End If |
120 | End Function |
121 | End If |
122 | Else |
123 | Dim range As New DoubleRange(from, [to]) |
124 | If forceInit Then |
125 | Return Function() New Random().NextDouble(range) |
126 | Else |
127 | Dim rnd As New Random |
128 | Return Function() rnd.NextDouble(range) |
129 | End If |
130 | End If |
131 | Else ' to 同样也是负数的情况 |
132 | If pf <> 0F OrElse pt <> 0F Then ' 两个都是极值数 |
133 | |
134 | pf = sys.Log10(sys.Abs(from)) |
135 | pt = sys.Log10(sys.Abs([to])) |
136 | |
137 | Dim c = {pf, pt} |
138 | Dim rnd As New PreciseRandom(c.Min, c.Max) ' 由于from要小于to |
139 | Return Function() -1 * rnd.NextNumber |
140 | Else ' from 和 to 都是负实数 |
141 | Dim range As New DoubleRange(from, [to]) |
142 | If forceInit Then |
143 | Return Function() New Random().NextDouble(range) |
144 | Else |
145 | Dim rnd As New Random |
146 | Return Function() rnd.NextDouble(range) |
147 | End If |
148 | End If |
149 | End If |
150 | End If |
151 | End Function |
152 | |
153 | Public Function Testing(from#, to#) As Double() |
154 | Dim rnd As IValueProvider = GetRandom(from, [to]) |
155 | Dim bufs As New List(Of Double) |
156 | |
157 | For Each i% In 1000%.Sequence |
158 | bufs += rnd() |
159 | Next |
160 | |
161 | Return bufs |
162 | End Function |
163 | End Module |
164 | End Namespace |