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: strandmark@google.com (Petter Strandmark) 30 31 #ifndef CERES_INTERNAL_CXSPARSE_H_ 32 #define CERES_INTERNAL_CXSPARSE_H_ 33 34 #ifndef CERES_NO_CXSPARSE 35 36 #include "cs.h" 37 38 namespace ceres { 39 namespace internal { 40 41 class CompressedRowSparseMatrix; 42 class TripletSparseMatrix; 43 44 // This object provides access to solving linear systems using Cholesky 45 // factorization with a known symbolic factorization. This features does not 46 // explicity exist in CXSparse. The methods in the class are nonstatic because 47 // the class manages internal scratch space. 48 class CXSparse { 49 public: 50 CXSparse(); 51 ~CXSparse(); 52 53 // Solves a symmetric linear system A * x = b using Cholesky factorization. 54 // A - The system matrix. 55 // symbolic_factorization - The symbolic factorization of A. This is obtained 56 // from AnalyzeCholesky. 57 // b - The right hand size of the linear equation. This 58 // array will also recieve the solution. 59 // Returns false if Cholesky factorization of A fails. 60 bool SolveCholesky(cs_di* A, cs_dis* symbolic_factorization, double* b); 61 62 // Creates a sparse matrix from a compressed-column form. No memory is 63 // allocated or copied; the structure A is filled out with info from the 64 // argument. 65 cs_di CreateSparseMatrixTransposeView(CompressedRowSparseMatrix* A); 66 67 // Creates a new matrix from a triplet form. Deallocate the returned matrix 68 // with Free. May return NULL if the compression or allocation fails. 69 cs_di* CreateSparseMatrix(TripletSparseMatrix* A); 70 71 // Computes a symbolic factorization of A that can be used in SolveCholesky. 72 // The returned matrix should be deallocated with Free when not used anymore. 73 cs_dis* AnalyzeCholesky(cs_di* A); 74 75 // Deallocates the memory of a matrix obtained from AnalyzeCholesky. 76 void Free(cs_di* factor); 77 void Free(cs_dis* factor); 78 79 private: 80 // Cached scratch space 81 CS_ENTRY* scratch_; 82 int scratch_size_; 83 }; 84 85 } // namespace internal 86 } // namespace ceres 87 88 #endif // CERES_NO_CXSPARSE 89 90 #endif // CERES_INTERNAL_CXSPARSE_H_ 91