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author | Nao Pross <np@0hm.ch> | 2024-02-12 14:52:43 +0100 |
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committer | Nao Pross <np@0hm.ch> | 2024-02-12 14:52:43 +0100 |
commit | eda5bc26f44ee9a6f83dcf8c91f17296d7fc509d (patch) | |
tree | bc2efa38ff4e350f9a111ac87065cd7ae9a911c7 /src/armadillo/include/armadillo_bits/newarp_DoubleShiftQR_bones.hpp | |
download | fsisotool-eda5bc26f44ee9a6f83dcf8c91f17296d7fc509d.tar.gz fsisotool-eda5bc26f44ee9a6f83dcf8c91f17296d7fc509d.zip |
Move into version control
Diffstat (limited to 'src/armadillo/include/armadillo_bits/newarp_DoubleShiftQR_bones.hpp')
-rw-r--r-- | src/armadillo/include/armadillo_bits/newarp_DoubleShiftQR_bones.hpp | 76 |
1 files changed, 76 insertions, 0 deletions
diff --git a/src/armadillo/include/armadillo_bits/newarp_DoubleShiftQR_bones.hpp b/src/armadillo/include/armadillo_bits/newarp_DoubleShiftQR_bones.hpp new file mode 100644 index 0000000..1599568 --- /dev/null +++ b/src/armadillo/include/armadillo_bits/newarp_DoubleShiftQR_bones.hpp @@ -0,0 +1,76 @@ +// SPDX-License-Identifier: Apache-2.0 +// +// Copyright 2008-2016 Conrad Sanderson (http://conradsanderson.id.au) +// Copyright 2008-2016 National ICT Australia (NICTA) +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. +// ------------------------------------------------------------------------ + + +namespace newarp +{ + + +template<typename eT> +class DoubleShiftQR + { + private: + + uword n; // Dimension of the matrix + Mat<eT> mat_H; // A copy of the matrix to be factorised + eT shift_s; // Shift constant + eT shift_t; // Shift constant + Mat<eT> ref_u; // Householder reflectors + Col<unsigned short> ref_nr; // How many rows does each reflector affects + // 3 - A general reflector + // 2 - A Givens rotation + // 1 - An identity transformation + const eT prec; // Approximately zero + const eT eps_rel; + const eT eps_abs; + bool computed; // Whether matrix has been factorised + + inline void compute_reflector(const eT& x1, const eT& x2, const eT& x3, uword ind); + arma_inline void compute_reflector(const eT* x, uword ind); + + // Update the block X = H(il:iu, il:iu) + inline void update_block(uword il, uword iu); + + // P = I - 2 * u * u' = P' + // PX = X - 2 * u * (u'X) + inline void apply_PX(Mat<eT>& X, uword oi, uword oj, uword nrow, uword ncol, uword u_ind); + + // x is a pointer to a vector + // Px = x - 2 * dot(x, u) * u + inline void apply_PX(eT* x, uword u_ind); + + // XP = X - 2 * (X * u) * u' + inline void apply_XP(Mat<eT>& X, uword oi, uword oj, uword nrow, uword ncol, uword u_ind); + + + public: + + inline DoubleShiftQR(uword size); + + inline DoubleShiftQR(const Mat<eT>& mat_obj, eT s, eT t); + + inline void compute(const Mat<eT>& mat_obj, eT s, eT t); + + inline Mat<eT> matrix_QtHQ(); + + inline void apply_QtY(Col<eT>& y); + + inline void apply_YQ(Mat<eT>& Y); + }; + + +} // namespace newarp |