1 // Ceres Solver - A fast non-linear least squares minimizer 2 // Copyright 2010, 2011, 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 // Block structure objects are used to carry information about the 32 // dense block structure of sparse matrices. The BlockSparseMatrix 33 // object uses the BlockStructure objects to keep track of the matrix 34 // structure and operate upon it. This allows us to use more cache 35 // friendly block oriented linear algebra operations on the matrix 36 // instead of accessing it one scalar entry at a time. 37 38 #ifndef CERES_INTERNAL_BLOCK_STRUCTURE_H_ 39 #define CERES_INTERNAL_BLOCK_STRUCTURE_H_ 40 41 #include <vector> 42 #include "ceres/internal/port.h" 43 #include "ceres/types.h" 44 45 namespace ceres { 46 namespace internal { 47 48 typedef int32 BlockSize; 49 50 struct Block { 51 Block() : size(-1), position(-1) {} 52 Block(int size_, int position_) : size(size_), position(position_) {} 53 54 BlockSize size; 55 int position; // Position along the row/column. 56 }; 57 58 struct Cell { 59 Cell() : block_id(-1), position(-1) {} 60 Cell(int block_id_, int position_) 61 : block_id(block_id_), position(position_) {} 62 63 // Column or row block id as the case maybe. 64 int block_id; 65 // Where in the values array of the jacobian is this cell located. 66 int position; 67 }; 68 69 // Order cell by their block_id; 70 bool CellLessThan(const Cell& lhs, const Cell& rhs); 71 72 struct CompressedList { 73 Block block; 74 vector<Cell> cells; 75 }; 76 77 typedef CompressedList CompressedRow; 78 typedef CompressedList CompressedColumn; 79 80 struct CompressedRowBlockStructure { 81 vector<Block> cols; 82 vector<CompressedRow> rows; 83 }; 84 85 struct CompressedColumnBlockStructure { 86 vector<Block> rows; 87 vector<CompressedColumn> cols; 88 }; 89 90 } // namespace internal 91 } // namespace ceres 92 93 #endif // CERES_INTERNAL_BLOCK_STRUCTURE_H_ 94
