|  | // Ceres Solver - A fast non-linear least squares minimizer | 
|  | // Copyright 2023 Google Inc. All rights reserved. | 
|  | // http://ceres-solver.org/ | 
|  | // | 
|  | // Redistribution and use in source and binary forms, with or without | 
|  | // modification, are permitted provided that the following conditions are met: | 
|  | // | 
|  | // * Redistributions of source code must retain the above copyright notice, | 
|  | //   this list of conditions and the following disclaimer. | 
|  | // * Redistributions in binary form must reproduce the above copyright notice, | 
|  | //   this list of conditions and the following disclaimer in the documentation | 
|  | //   and/or other materials provided with the distribution. | 
|  | // * Neither the name of Google Inc. nor the names of its contributors may be | 
|  | //   used to endorse or promote products derived from this software without | 
|  | //   specific prior written permission. | 
|  | // | 
|  | // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" | 
|  | // AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | 
|  | // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | 
|  | // ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE | 
|  | // LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR | 
|  | // CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF | 
|  | // SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS | 
|  | // INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN | 
|  | // CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) | 
|  | // ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE | 
|  | // POSSIBILITY OF SUCH DAMAGE. | 
|  | // | 
|  | // Author: sameeragarwal@google.com (Sameer Agarwal) | 
|  | // | 
|  | // A simple C++ interface to the SuiteSparse and CHOLMOD libraries. | 
|  |  | 
|  | #ifndef CERES_INTERNAL_SUITESPARSE_H_ | 
|  | #define CERES_INTERNAL_SUITESPARSE_H_ | 
|  |  | 
|  | // This include must come before any #ifndef check on Ceres compile options. | 
|  | #include "ceres/internal/config.h" | 
|  |  | 
|  | #ifndef CERES_NO_SUITESPARSE | 
|  |  | 
|  | #include <cstring> | 
|  | #include <memory> | 
|  | #include <string> | 
|  | #include <vector> | 
|  |  | 
|  | #include "SuiteSparseQR.hpp" | 
|  | #include "ceres/block_structure.h" | 
|  | #include "ceres/internal/disable_warnings.h" | 
|  | #include "ceres/linear_solver.h" | 
|  | #include "ceres/sparse_cholesky.h" | 
|  | #include "cholmod.h" | 
|  | #include "glog/logging.h" | 
|  |  | 
|  | namespace ceres::internal { | 
|  |  | 
|  | class CompressedRowSparseMatrix; | 
|  | class TripletSparseMatrix; | 
|  |  | 
|  | // The raw CHOLMOD and SuiteSparseQR libraries have a slightly | 
|  | // cumbersome c like calling format. This object abstracts it away and | 
|  | // provides the user with a simpler interface. The methods here cannot | 
|  | // be static as a cholmod_common object serves as a global variable | 
|  | // for all cholmod function calls. | 
|  | class CERES_NO_EXPORT SuiteSparse { | 
|  | public: | 
|  | SuiteSparse(); | 
|  | ~SuiteSparse(); | 
|  |  | 
|  | // Functions for building cholmod_sparse objects from sparse | 
|  | // matrices stored in triplet form. The matrix A is not | 
|  | // modified. Called owns the result. | 
|  | cholmod_sparse* CreateSparseMatrix(TripletSparseMatrix* A); | 
|  |  | 
|  | // This function works like CreateSparseMatrix, except that the | 
|  | // return value corresponds to A' rather than A. | 
|  | cholmod_sparse* CreateSparseMatrixTranspose(TripletSparseMatrix* A); | 
|  |  | 
|  | // Create a cholmod_sparse wrapper around the contents of A. This is | 
|  | // a shallow object, which refers to the contents of A and does not | 
|  | // use the SuiteSparse machinery to allocate memory. | 
|  | cholmod_sparse CreateSparseMatrixTransposeView(CompressedRowSparseMatrix* A); | 
|  |  | 
|  | // Create a cholmod_dense vector around the contents of the array x. | 
|  | // This is a shallow object, which refers to the contents of x and | 
|  | // does not use the SuiteSparse machinery to allocate memory. | 
|  | cholmod_dense CreateDenseVectorView(const double* x, int size); | 
|  |  | 
|  | // Given a vector x, build a cholmod_dense vector of size out_size | 
|  | // with the first in_size entries copied from x. If x is nullptr, then | 
|  | // an all zeros vector is returned. Caller owns the result. | 
|  | cholmod_dense* CreateDenseVector(const double* x, int in_size, int out_size); | 
|  |  | 
|  | // The matrix A is scaled using the matrix whose diagonal is the | 
|  | // vector scale. mode describes how scaling is applied. Possible | 
|  | // values are CHOLMOD_ROW for row scaling - diag(scale) * A, | 
|  | // CHOLMOD_COL for column scaling - A * diag(scale) and CHOLMOD_SYM | 
|  | // for symmetric scaling which scales both the rows and the columns | 
|  | // - diag(scale) * A * diag(scale). | 
|  | void Scale(cholmod_dense* scale, int mode, cholmod_sparse* A) { | 
|  | cholmod_scale(scale, mode, A, &cc_); | 
|  | } | 
|  |  | 
|  | // Create and return a matrix m = A * A'. Caller owns the | 
|  | // result. The matrix A is not modified. | 
|  | cholmod_sparse* AATranspose(cholmod_sparse* A) { | 
|  | cholmod_sparse* m = cholmod_aat(A, nullptr, A->nrow, 1, &cc_); | 
|  | m->stype = 1;  // Pay attention to the upper triangular part. | 
|  | return m; | 
|  | } | 
|  |  | 
|  | // y = alpha * A * x + beta * y. Only y is modified. | 
|  | void SparseDenseMultiply(cholmod_sparse* A, | 
|  | double alpha, | 
|  | double beta, | 
|  | cholmod_dense* x, | 
|  | cholmod_dense* y) { | 
|  | double alpha_[2] = {alpha, 0}; | 
|  | double beta_[2] = {beta, 0}; | 
|  | cholmod_sdmult(A, 0, alpha_, beta_, x, y, &cc_); | 
|  | } | 
|  |  | 
|  | // Compute a symbolic factorization for A or AA' (if A is | 
|  | // unsymmetric). If ordering_type is NATURAL, then no fill reducing | 
|  | // ordering is computed, otherwise depending on the value of | 
|  | // ordering_type AMD or Nested Dissection is used to compute a fill | 
|  | // reducing ordering before the symbolic factorization is computed. | 
|  | // | 
|  | // A is not modified, only the pattern of non-zeros of A is used, | 
|  | // the actual numerical values in A are of no consequence. | 
|  | // | 
|  | // message contains an explanation of the failures if any. | 
|  | // | 
|  | // Caller owns the result. | 
|  | cholmod_factor* AnalyzeCholesky(cholmod_sparse* A, | 
|  | OrderingType ordering_type, | 
|  | std::string* message); | 
|  |  | 
|  | // Block oriented version of AnalyzeCholesky. | 
|  | cholmod_factor* BlockAnalyzeCholesky(cholmod_sparse* A, | 
|  | OrderingType ordering_type, | 
|  | const std::vector<Block>& row_blocks, | 
|  | const std::vector<Block>& col_blocks, | 
|  | std::string* message); | 
|  |  | 
|  | // If A is symmetric, then compute the symbolic Cholesky | 
|  | // factorization of A(ordering, ordering). If A is unsymmetric, then | 
|  | // compute the symbolic factorization of | 
|  | // A(ordering,:) A(ordering,:)'. | 
|  | // | 
|  | // A is not modified, only the pattern of non-zeros of A is used, | 
|  | // the actual numerical values in A are of no consequence. | 
|  | // | 
|  | // message contains an explanation of the failures if any. | 
|  | // | 
|  | // Caller owns the result. | 
|  | cholmod_factor* AnalyzeCholeskyWithGivenOrdering( | 
|  | cholmod_sparse* A, | 
|  | const std::vector<int>& ordering, | 
|  | std::string* message); | 
|  |  | 
|  | // Use the symbolic factorization in L, to find the numerical | 
|  | // factorization for the matrix A or AA^T. Return true if | 
|  | // successful, false otherwise. L contains the numeric factorization | 
|  | // on return. | 
|  | // | 
|  | // message contains an explanation of the failures if any. | 
|  | LinearSolverTerminationType Cholesky(cholmod_sparse* A, | 
|  | cholmod_factor* L, | 
|  | std::string* message); | 
|  |  | 
|  | // Given a Cholesky factorization of a matrix A = LL^T, solve the | 
|  | // linear system Ax = b, and return the result. If the Solve fails | 
|  | // nullptr is returned. Caller owns the result. | 
|  | // | 
|  | // message contains an explanation of the failures if any. | 
|  | cholmod_dense* Solve(cholmod_factor* L, | 
|  | cholmod_dense* b, | 
|  | std::string* message); | 
|  |  | 
|  | // Find a fill reducing ordering. ordering is expected to be large | 
|  | // enough to hold the ordering. ordering_type must be AMD or NESDIS. | 
|  | bool Ordering(cholmod_sparse* matrix, | 
|  | OrderingType ordering_type, | 
|  | int* ordering); | 
|  |  | 
|  | // Find the block oriented fill reducing ordering of a matrix A, | 
|  | // whose row and column blocks are given by row_blocks, and | 
|  | // col_blocks respectively. The matrix may or may not be | 
|  | // symmetric. The entries of col_blocks do not need to sum to the | 
|  | // number of columns in A. If this is the case, only the first | 
|  | // sum(col_blocks) are used to compute the ordering. | 
|  | // | 
|  | // By virtue of the modeling layer in Ceres being block oriented, | 
|  | // all the matrices used by Ceres are also block oriented. When | 
|  | // doing sparse direct factorization of these matrices the | 
|  | // fill-reducing ordering algorithms can either be run on the block | 
|  | // or the scalar form of these matrices. But since the underlying | 
|  | // matrices are block oriented, it is worth running the fill | 
|  | // reducing ordering on just the block structure of these matrices | 
|  | // and then lifting these block orderings to a full scalar | 
|  | // ordering. This preserves the block structure of the permuted | 
|  | // matrix, and exposes more of the super-nodal structure of the | 
|  | // matrix to the numerical factorization routines. | 
|  | bool BlockOrdering(const cholmod_sparse* A, | 
|  | OrderingType ordering_type, | 
|  | const std::vector<Block>& row_blocks, | 
|  | const std::vector<Block>& col_blocks, | 
|  | std::vector<int>* ordering); | 
|  |  | 
|  | // Nested dissection is only available if SuiteSparse is compiled | 
|  | // with Metis support. | 
|  | static bool IsNestedDissectionAvailable(); | 
|  |  | 
|  | // Find a fill reducing approximate minimum degree | 
|  | // ordering. constraints is an array which associates with each | 
|  | // column of the matrix an elimination group. i.e., all columns in | 
|  | // group 0 are eliminated first, all columns in group 1 are | 
|  | // eliminated next etc. This function finds a fill reducing ordering | 
|  | // that obeys these constraints. | 
|  | // | 
|  | // Calling ApproximateMinimumDegreeOrdering is equivalent to calling | 
|  | // ConstrainedApproximateMinimumDegreeOrdering with a constraint | 
|  | // array that puts all columns in the same elimination group. | 
|  | bool ConstrainedApproximateMinimumDegreeOrdering(cholmod_sparse* matrix, | 
|  | int* constraints, | 
|  | int* ordering); | 
|  |  | 
|  | void Free(cholmod_sparse* m) { cholmod_free_sparse(&m, &cc_); } | 
|  | void Free(cholmod_dense* m) { cholmod_free_dense(&m, &cc_); } | 
|  | void Free(cholmod_factor* m) { cholmod_free_factor(&m, &cc_); } | 
|  |  | 
|  | void Print(cholmod_sparse* m, const std::string& name) { | 
|  | cholmod_print_sparse(m, const_cast<char*>(name.c_str()), &cc_); | 
|  | } | 
|  |  | 
|  | void Print(cholmod_dense* m, const std::string& name) { | 
|  | cholmod_print_dense(m, const_cast<char*>(name.c_str()), &cc_); | 
|  | } | 
|  |  | 
|  | void Print(cholmod_triplet* m, const std::string& name) { | 
|  | cholmod_print_triplet(m, const_cast<char*>(name.c_str()), &cc_); | 
|  | } | 
|  |  | 
|  | cholmod_common* mutable_cc() { return &cc_; } | 
|  |  | 
|  | private: | 
|  | cholmod_common cc_; | 
|  | }; | 
|  |  | 
|  | class CERES_NO_EXPORT SuiteSparseCholesky final : public SparseCholesky { | 
|  | public: | 
|  | static std::unique_ptr<SparseCholesky> Create(OrderingType ordering_type); | 
|  |  | 
|  | // SparseCholesky interface. | 
|  | ~SuiteSparseCholesky() override; | 
|  | CompressedRowSparseMatrix::StorageType StorageType() const final; | 
|  | LinearSolverTerminationType Factorize(CompressedRowSparseMatrix* lhs, | 
|  | std::string* message) final; | 
|  | LinearSolverTerminationType Solve(const double* rhs, | 
|  | double* solution, | 
|  | std::string* message) final; | 
|  |  | 
|  | private: | 
|  | explicit SuiteSparseCholesky(const OrderingType ordering_type); | 
|  |  | 
|  | const OrderingType ordering_type_; | 
|  | SuiteSparse ss_; | 
|  | cholmod_factor* factor_; | 
|  | }; | 
|  |  | 
|  | }  // namespace ceres::internal | 
|  |  | 
|  | #include "ceres/internal/reenable_warnings.h" | 
|  |  | 
|  | #else  // CERES_NO_SUITESPARSE | 
|  |  | 
|  | using cholmod_factor = void; | 
|  |  | 
|  | #include "ceres/internal/disable_warnings.h" | 
|  |  | 
|  | namespace ceres { | 
|  | namespace internal { | 
|  |  | 
|  | class CERES_NO_EXPORT SuiteSparse { | 
|  | public: | 
|  | // Nested dissection is only available if SuiteSparse is compiled | 
|  | // with Metis support. | 
|  | static bool IsNestedDissectionAvailable() { return false; } | 
|  | void Free(void* /*arg*/) {} | 
|  | }; | 
|  |  | 
|  | }  // namespace internal | 
|  | }  // namespace ceres | 
|  |  | 
|  | #include "ceres/internal/reenable_warnings.h" | 
|  |  | 
|  | #endif  // CERES_NO_SUITESPARSE | 
|  |  | 
|  | #endif  // CERES_INTERNAL_SUITESPARSE_H_ |