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Diffstat (limited to 'internal/ceres/cxsparse.cc')
-rw-r--r-- | internal/ceres/cxsparse.cc | 130 |
1 files changed, 130 insertions, 0 deletions
diff --git a/internal/ceres/cxsparse.cc b/internal/ceres/cxsparse.cc new file mode 100644 index 0000000..21c98e0 --- /dev/null +++ b/internal/ceres/cxsparse.cc @@ -0,0 +1,130 @@ +// Ceres Solver - A fast non-linear least squares minimizer +// Copyright 2012 Google Inc. All rights reserved. +// http://code.google.com/p/ceres-solver/ +// +// 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: strandmark@google.com (Petter Strandmark) + +#ifndef CERES_NO_CXSPARSE + +#include "ceres/cxsparse.h" + +#include "ceres/compressed_row_sparse_matrix.h" +#include "ceres/triplet_sparse_matrix.h" +#include "glog/logging.h" + +namespace ceres { +namespace internal { + +CXSparse::CXSparse() : scratch_(NULL), scratch_size_(0) { +} + +CXSparse::~CXSparse() { + if (scratch_size_ > 0) { + cs_free(scratch_); + } +} + +bool CXSparse::SolveCholesky(cs_di* A, + cs_dis* symbolic_factorization, + double* b) { + // Make sure we have enough scratch space available. + if (scratch_size_ < A->n) { + if (scratch_size_ > 0) { + cs_free(scratch_); + } + scratch_ = reinterpret_cast<CS_ENTRY*>(cs_malloc(A->n, sizeof(CS_ENTRY))); + } + + // Solve using Cholesky factorization + csn* numeric_factorization = cs_chol(A, symbolic_factorization); + if (numeric_factorization == NULL) { + LOG(WARNING) << "Cholesky factorization failed."; + return false; + } + + // When the Cholesky factorization succeeded, these methods are guaranteed to + // succeeded as well. In the comments below, "x" refers to the scratch space. + // + // Set x = P * b. + cs_ipvec(symbolic_factorization->pinv, b, scratch_, A->n); + + // Set x = L \ x. + cs_lsolve(numeric_factorization->L, scratch_); + + // Set x = L' \ x. + cs_ltsolve(numeric_factorization->L, scratch_); + + // Set b = P' * x. + cs_pvec(symbolic_factorization->pinv, scratch_, b, A->n); + + // Free Cholesky factorization. + cs_nfree(numeric_factorization); + return true; +} + +cs_dis* CXSparse::AnalyzeCholesky(cs_di* A) { + // order = 1 for Cholesky factorization. + return cs_schol(1, A); +} + +cs_di CXSparse::CreateSparseMatrixTransposeView(CompressedRowSparseMatrix* A) { + cs_di At; + At.m = A->num_cols(); + At.n = A->num_rows(); + At.nz = -1; + At.nzmax = A->num_nonzeros(); + At.p = A->mutable_rows(); + At.i = A->mutable_cols(); + At.x = A->mutable_values(); + return At; +} + +cs_di* CXSparse::CreateSparseMatrix(TripletSparseMatrix* tsm) { + cs_di_sparse tsm_wrapper; + tsm_wrapper.nzmax = tsm->num_nonzeros();; + tsm_wrapper.nz = tsm->num_nonzeros();; + tsm_wrapper.m = tsm->num_rows(); + tsm_wrapper.n = tsm->num_cols(); + tsm_wrapper.p = tsm->mutable_cols(); + tsm_wrapper.i = tsm->mutable_rows(); + tsm_wrapper.x = tsm->mutable_values(); + + return cs_compress(&tsm_wrapper); +} + +void CXSparse::Free(cs_di* factor) { + cs_free(factor); +} + +void CXSparse::Free(cs_dis* factor) { + cs_sfree(factor); +} + +} // namespace internal +} // namespace ceres + +#endif // CERES_NO_CXSPARSE |