1 | #Region "Microsoft.VisualBasic::8e82f2529ec9f0bcd074d4defebc0b2d, Microsoft.VisualBasic.Core\Extensions\Math\Matrix.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 MatrixExtensions |
35 | ' |
36 | ' Function: MatrixMult, ScalarMult |
37 | ' |
38 | ' |
39 | ' /********************************************************************************/ |
40 | |
41 | #End Region |
42 | |
43 | ' Copyright Jean-Francois Larcher-Pelland 2013-2014 |
44 | ' Distributed under the Boost Software License, Version 1.0. |
45 | ' (See accompanying file LICENSE_1_0.txt or copy at |
46 | ' http://www.boost.org/LICENSE_1_0.txt) |
47 | |
48 | Namespace Math |
49 | |
50 | ''' <summary> |
51 | ''' This class contains methods that perform mathematical operations on matrices. |
52 | ''' Operations currently supported are matrix multiplication and scalar multiplication. |
53 | ''' |
54 | ''' @author Jean-Francois Larcher-Pelland |
55 | ''' </summary> |
56 | Public Module MatrixExtensions |
57 | |
58 | ''' <summary> |
59 | ''' Multiplies matrices <i>a</i> and <i>b</i> using the brute-force algorithm. |
60 | ''' </summary> |
61 | ''' <param name="a"> The matrix on the left. </param> |
62 | ''' <param name="b"> The matrix on the right. </param> |
63 | ''' <returns> The product of the two matrices. </returns> |
64 | Public Function MatrixMult(a As Double()(), b As Double()()) As Double()() |
65 | If a Is Nothing OrElse b Is Nothing Then |
66 | Throw New ArgumentException("One or both input matrices are null") |
67 | ElseIf a(0).Length <> b.Length Then |
68 | Throw New ArgumentException("Column count of left matrix not equal to row count of right matrix.") |
69 | End If |
70 | Dim row As Integer = a.Length |
71 | Dim col As Integer = b(0).Length |
72 | Dim inner As Integer = b.Length |
73 | Dim out As Double()() = MAT(Of Double)(row, col) |
74 | For i As Integer = 0 To row - 1 |
75 | For j As Integer = 0 To col - 1 |
76 | For k As Integer = 0 To inner - 1 |
77 | out(i)(j) += a(i)(k) * b(k)(j) |
78 | Next |
79 | Next |
80 | Next |
81 | Return out |
82 | End Function |
83 | |
84 | ''' <summary> |
85 | ''' Performs a scalar multiplication on matrix <i>a</i> using scalar value <i>b</i>. |
86 | ''' </summary> |
87 | ''' <param name="a"> The matrix to be multiplied. </param> |
88 | ''' <param name="b"> Scalar value used in the multiplication. </param> |
89 | ''' <returns> The result of the scalar multiplication. </returns> |
90 | Public Function ScalarMult(a As Double()(), b As Double) As Double()() |
91 | If a Is Nothing Then |
92 | Throw New ArgumentException("Input matrix is null") |
93 | End If |
94 | Dim out As Double()() = MAT(Of Double)(a.Length, a(0).Length) |
95 | For i As Integer = 0 To out.Length - 1 |
96 | For j As Integer = 0 To out(0).Length - 1 |
97 | out(i)(j) = a(i)(j) * b |
98 | Next |
99 | Next |
100 | Return out |
101 | End Function |
102 | End Module |
103 | End Namespace |