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Diffstat (limited to 'eigen/Eigen/src/SparseLU/SparseLU_Utils.h')
-rw-r--r-- | eigen/Eigen/src/SparseLU/SparseLU_Utils.h | 80 |
1 files changed, 80 insertions, 0 deletions
diff --git a/eigen/Eigen/src/SparseLU/SparseLU_Utils.h b/eigen/Eigen/src/SparseLU/SparseLU_Utils.h new file mode 100644 index 0000000..15352ac --- /dev/null +++ b/eigen/Eigen/src/SparseLU/SparseLU_Utils.h @@ -0,0 +1,80 @@ +// This file is part of Eigen, a lightweight C++ template library +// for linear algebra. +// +// Copyright (C) 2012 Désiré Nuentsa-Wakam <desire.nuentsa_wakam@inria.fr> +// +// This Source Code Form is subject to the terms of the Mozilla +// Public License v. 2.0. If a copy of the MPL was not distributed +// with this file, You can obtain one at http://mozilla.org/MPL/2.0/. + + +#ifndef EIGEN_SPARSELU_UTILS_H +#define EIGEN_SPARSELU_UTILS_H + +namespace Eigen { +namespace internal { + +/** + * \brief Count Nonzero elements in the factors + */ +template <typename Scalar, typename Index> +void SparseLUImpl<Scalar,Index>::countnz(const Index n, Index& nnzL, Index& nnzU, GlobalLU_t& glu) +{ + nnzL = 0; + nnzU = (glu.xusub)(n); + Index nsuper = (glu.supno)(n); + Index jlen; + Index i, j, fsupc; + if (n <= 0 ) return; + // For each supernode + for (i = 0; i <= nsuper; i++) + { + fsupc = glu.xsup(i); + jlen = glu.xlsub(fsupc+1) - glu.xlsub(fsupc); + + for (j = fsupc; j < glu.xsup(i+1); j++) + { + nnzL += jlen; + nnzU += j - fsupc + 1; + jlen--; + } + } +} + +/** + * \brief Fix up the data storage lsub for L-subscripts. + * + * It removes the subscripts sets for structural pruning, + * and applies permutation to the remaining subscripts + * + */ +template <typename Scalar, typename Index> +void SparseLUImpl<Scalar,Index>::fixupL(const Index n, const IndexVector& perm_r, GlobalLU_t& glu) +{ + Index fsupc, i, j, k, jstart; + + Index nextl = 0; + Index nsuper = (glu.supno)(n); + + // For each supernode + for (i = 0; i <= nsuper; i++) + { + fsupc = glu.xsup(i); + jstart = glu.xlsub(fsupc); + glu.xlsub(fsupc) = nextl; + for (j = jstart; j < glu.xlsub(fsupc + 1); j++) + { + glu.lsub(nextl) = perm_r(glu.lsub(j)); // Now indexed into P*A + nextl++; + } + for (k = fsupc+1; k < glu.xsup(i+1); k++) + glu.xlsub(k) = nextl; // other columns in supernode i + } + + glu.xlsub(n) = nextl; +} + +} // end namespace internal + +} // end namespace Eigen +#endif // EIGEN_SPARSELU_UTILS_H |