GDAL

gdallinearsystem.h
1/******************************************************************************
2 *
3 * Project: GDAL
4 * Purpose: Linear system solver
5 * Author: VIZRT Development Team.
6 *
7 ******************************************************************************
8 * Copyright (c) 2017 Alan Thomas <alant@outlook.com.au>
9 *
10 * Permission is hereby granted, free of charge, to any person obtaining a
11 * copy of this software and associated documentation files (the "Software"),
12 * to deal in the Software without restriction, including without limitation
13 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
14 * and/or sell copies of the Software, and to permit persons to whom the
15 * Software is furnished to do so, subject to the following conditions:
16 *
17 * The above copyright notice and this permission notice shall be included
18 * in all copies or substantial portions of the Software.
19 *
20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
21 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
23 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
24 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
25 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
26 * DEALINGS IN THE SOFTWARE.
27 ****************************************************************************/
28
31#ifndef GDALLINEARSYSTEM_H_INCLUDED
32#define GDALLINEARSYSTEM_H_INCLUDED
33
34#include <vector>
35
36/*
37 * Matrix class with double entries.
38 * The elements are stored in column major order in a vector.
39 */
40struct GDALMatrix
41{
43 GDALMatrix() = default;
44
47 GDALMatrix(int rows, int cols)
48 : n_rows(rows), n_cols(cols), v(rows * cols, 0.)
49 {
50 }
51
53 inline int getNumRows() const
54 {
55 return n_rows;
56 }
57
59 inline int getNumCols() const
60 {
61 return n_cols;
62 }
63
65 inline double &operator()(int row, int col)
66 {
67 return v[row + col * static_cast<size_t>(n_rows)];
68 }
69
71 inline double operator()(int row, int col) const
72 {
73 return v[row + col * static_cast<size_t>(n_rows)];
74 }
75
77 double const *data() const
78 {
79 return v.data();
80 }
81
83 double *data()
84 {
85 return v.data();
86 }
87
89 void resize(int iRows, int iCols)
90 {
91 n_rows = iRows;
92 n_cols = iCols;
93 v.clear();
94 v.resize(static_cast<size_t>(iRows) * iCols);
95 }
96
97 private:
98 int n_rows = 0;
99 int n_cols = 0;
100 std::vector<double> v;
101};
102
103bool GDALLinearSystemSolve(GDALMatrix &A, GDALMatrix &RHS, GDALMatrix &X);
104
105#endif /* #ifndef GDALLINEARSYSTEM_H_INCLUDED */
106