1 //////////////////////////////////////////////////////////////////////// 2 // 3 // Copyright (C) 1994-2021 The Octave Project Developers 4 // 5 // See the file COPYRIGHT.md in the top-level directory of this 6 // distribution or <https://octave.org/copyright/>. 7 // 8 // This file is part of Octave. 9 // 10 // Octave is free software: you can redistribute it and/or modify it 11 // under the terms of the GNU General Public License as published by 12 // the Free Software Foundation, either version 3 of the License, or 13 // (at your option) any later version. 14 // 15 // Octave is distributed in the hope that it will be useful, but 16 // WITHOUT ANY WARRANTY; without even the implied warranty of 17 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 18 // GNU General Public License for more details. 19 // 20 // You should have received a copy of the GNU General Public License 21 // along with Octave; see the file COPYING. If not, see 22 // <https://www.gnu.org/licenses/>. 23 // 24 //////////////////////////////////////////////////////////////////////// 25 26 #if ! defined (octave_aepbalance_h) 27 #define octave_aepbalance_h 1 28 29 #include "octave-config.h" 30 31 #include <algorithm> 32 33 namespace octave 34 { 35 namespace math 36 { 37 template <typename MT> 38 class aepbalance 39 { 40 public: 41 42 typedef typename MT::real_column_vector_type VT; 43 aepbalance(void)44 aepbalance (void) : balanced_mat (), scale (), ilo (), ihi (), job () { } 45 46 aepbalance (const MT& a, bool noperm = false, bool noscal = false); 47 aepbalance(const aepbalance & a)48 aepbalance (const aepbalance& a) 49 : balanced_mat (a.balanced_mat), scale (a.scale), 50 ilo(a.ilo), ihi(a.ihi), job(a.job) 51 { } 52 53 aepbalance& operator = (const aepbalance& a) 54 { 55 if (this != &a) 56 { 57 balanced_mat = a.balanced_mat; 58 scale = a.scale; 59 ilo = a.ilo; 60 ihi = a.ihi; 61 job = a.job; 62 } 63 64 return *this; 65 } 66 67 virtual ~aepbalance (void) = default; 68 69 MT balancing_matrix (void) const; 70 balanced_matrix(void)71 MT balanced_matrix (void) const 72 { 73 return balanced_mat; 74 } 75 permuting_vector(void)76 VT permuting_vector (void) const 77 { 78 octave_idx_type n = balanced_mat.rows (); 79 80 VT pv (n); 81 82 for (octave_idx_type i = 0; i < n; i++) 83 pv(i) = i+1; 84 85 for (octave_idx_type i = n-1; i >= ihi; i--) 86 { 87 octave_idx_type j = scale(i) - 1; 88 std::swap (pv(i), pv(j)); 89 } 90 91 for (octave_idx_type i = 0; i < ilo-1; i++) 92 { 93 octave_idx_type j = scale(i) - 1; 94 std::swap (pv(i), pv(j)); 95 } 96 97 return pv; 98 } 99 scaling_vector(void)100 VT scaling_vector (void) const 101 { 102 octave_idx_type n = balanced_mat.rows (); 103 104 VT scv (n); 105 106 for (octave_idx_type i = 0; i < ilo-1; i++) 107 scv(i) = 1; 108 109 for (octave_idx_type i = ilo-1; i < ihi; i++) 110 scv(i) = scale(i); 111 112 for (octave_idx_type i = ihi; i < n; i++) 113 scv(i) = 1; 114 115 return scv; 116 } 117 118 protected: 119 120 MT balanced_mat; 121 VT scale; 122 octave_idx_type ilo; 123 octave_idx_type ihi; 124 char job; 125 }; 126 } 127 } 128 129 #endif 130