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 * Matrix class with double entries.
37 * The elements are stored in column major order in a vector.
38 */
39 struct GDALMatrix
40 {
42  GDALMatrix() = default;
45  GDALMatrix(int rows, int cols) : n_rows(rows), n_cols(cols), v(rows * cols, 0.) {}
47  inline int getNumRows() const { return n_rows; }
49  inline int getNumCols() const { return n_cols; }
51  inline double & operator()(int row, int col) { return v[row + col * n_rows]; }
53  inline double operator()(int row, int col) const { return v[row + col * n_rows]; }
55  double const * data() const { return v.data(); }
57  double * data() { return v.data(); }
59  void resize(int iRows, int iCols)
60  {
61  n_rows = iRows;
62  n_cols = iCols;
63  v.clear();
64  v.resize(iRows * iCols);
65  }
66 private:
67  int n_rows = 0;
68  int n_cols = 0;
69  std::vector<double> v;
70 };
71 
72 bool GDALLinearSystemSolve( GDALMatrix & A, GDALMatrix & RHS, GDALMatrix & X );
73 
74 
75 #endif /* #ifndef GDALLINEARSYSTEM_H_INCLUDED */
76