1 // Ceres Solver - A fast non-linear least squares minimizer 2 // Copyright 2012 Google Inc. All rights reserved. 3 // http://code.google.com/p/ceres-solver/ 4 // 5 // Redistribution and use in source and binary forms, with or without 6 // modification, are permitted provided that the following conditions are met: 7 // 8 // * Redistributions of source code must retain the above copyright notice, 9 // this list of conditions and the following disclaimer. 10 // * Redistributions in binary form must reproduce the above copyright notice, 11 // this list of conditions and the following disclaimer in the documentation 12 // and/or other materials provided with the distribution. 13 // * Neither the name of Google Inc. nor the names of its contributors may be 14 // used to endorse or promote products derived from this software without 15 // specific prior written permission. 16 // 17 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 18 // AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 // ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 21 // LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 22 // CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 23 // SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 24 // INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 25 // CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 26 // ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 27 // POSSIBILITY OF SUCH DAMAGE. 28 // 29 // Author: sameeragarwal (at) google.com (Sameer Agarwal) 30 31 #ifndef CERES_PUBLIC_CRS_MATRIX_H_ 32 #define CERES_PUBLIC_CRS_MATRIX_H_ 33 34 #include <vector> 35 #include "ceres/internal/port.h" 36 37 namespace ceres { 38 39 // A compressed row sparse matrix used primarily for communicating the 40 // Jacobian matrix to the user. 41 struct CRSMatrix { 42 CRSMatrix() : num_rows(0), num_cols(0) {} 43 44 int num_rows; 45 int num_cols; 46 47 // A compressed row matrix stores its contents in three arrays, 48 // rows, cols and values. 49 // 50 // rows is a num_rows + 1 sized array that points into the cols and 51 // values array. For each row i: 52 // 53 // cols[rows[i]] ... cols[rows[i + 1] - 1] are the indices of the 54 // non-zero columns of row i. 55 // 56 // values[rows[i]] .. values[rows[i + 1] - 1] are the values of the 57 // corresponding entries. 58 // 59 // cols and values contain as many entries as there are non-zeros in 60 // the matrix. 61 // 62 // e.g, consider the 3x4 sparse matrix 63 // 64 // [ 0 10 0 4 ] 65 // [ 0 2 -3 2 ] 66 // [ 1 2 0 0 ] 67 // 68 // The three arrays will be: 69 // 70 // 71 // -row0- ---row1--- -row2- 72 // rows = [ 0, 2, 5, 7] 73 // cols = [ 1, 3, 1, 2, 3, 0, 1] 74 // values = [10, 4, 2, -3, 2, 1, 2] 75 76 vector<int> cols; 77 vector<int> rows; 78 vector<double> values; 79 }; 80 81 } // namespace ceres 82 83 #endif // CERES_PUBLIC_CRS_MATRIX_H_ 84
