GNU Octave  3.8.0
A high-level interpreted language, primarily intended for numerical computations, mostly compatible with Matlab
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CmplxGEPBAL.cc
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1 /*
2 
3 Copyright (C) 1994-2013 John W. Eaton
4 
5 This file is part of Octave.
6 
7 Octave is free software; you can redistribute it and/or modify it
8 under the terms of the GNU General Public License as published by the
9 Free Software Foundation; either version 3 of the License, or (at your
10 option) any later version.
11 
12 Octave is distributed in the hope that it will be useful, but WITHOUT
13 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 for more details.
16 
17 You should have received a copy of the GNU General Public License
18 along with Octave; see the file COPYING. If not, see
19 <http://www.gnu.org/licenses/>.
20 
21 */
22 
23 #ifdef HAVE_CONFIG_H
24 #include <config.h>
25 #endif
26 
27 #include <string>
28 #include <vector>
29 
30 #include "CmplxGEPBAL.h"
31 #include "Array-util.h"
32 #include "f77-fcn.h"
33 #include "oct-locbuf.h"
34 
35 extern "C"
36 {
37  F77_RET_T
38  F77_FUNC (zggbal, ZGGBAL) (F77_CONST_CHAR_ARG_DECL,
40  const octave_idx_type& LDA, Complex* B,
41  const octave_idx_type& LDB,
43  double* LSCALE, double* RSCALE,
44  double* WORK, octave_idx_type& INFO
46 
47  F77_RET_T
48  F77_FUNC (dggbak, DGGBAK) (F77_CONST_CHAR_ARG_DECL,
50  const octave_idx_type& N,
51  const octave_idx_type& ILO,
52  const octave_idx_type& IHI,
53  const double* LSCALE, const double* RSCALE,
54  octave_idx_type& M, double* V,
55  const octave_idx_type& LDV, octave_idx_type& INFO
58 
59 }
60 
63  const std::string& balance_job)
64 {
65  octave_idx_type n = a.cols ();
66 
67  if (a.rows () != n)
68  {
69  (*current_liboctave_error_handler)
70  ("ComplexGEPBALANCE requires square matrix");
71  return -1;
72  }
73 
74  if (a.dims () != b.dims ())
75  {
76  gripe_nonconformant ("ComplexGEPBALANCE", n, n, b.rows(), b.cols());
77  return -1;
78  }
79 
80  octave_idx_type info;
81  octave_idx_type ilo;
82  octave_idx_type ihi;
83 
84  OCTAVE_LOCAL_BUFFER (double, plscale, n);
85  OCTAVE_LOCAL_BUFFER (double, prscale, n);
86  OCTAVE_LOCAL_BUFFER (double, pwork, 6 * n);
87 
88  balanced_mat = a;
89  Complex *p_balanced_mat = balanced_mat.fortran_vec ();
90  balanced_mat2 = b;
91  Complex *p_balanced_mat2 = balanced_mat2.fortran_vec ();
92 
93  char job = balance_job[0];
94 
95  F77_XFCN (zggbal, ZGGBAL, (F77_CONST_CHAR_ARG2 (&job, 1),
96  n, p_balanced_mat, n, p_balanced_mat2,
97  n, ilo, ihi, plscale, prscale, pwork, info
98  F77_CHAR_ARG_LEN (1)));
99 
100  balancing_mat = Matrix (n, n, 0.0);
101  balancing_mat2 = Matrix (n, n, 0.0);
102  for (octave_idx_type i = 0; i < n; i++)
103  {
104  octave_quit ();
105  balancing_mat.elem (i ,i) = 1.0;
106  balancing_mat2.elem (i ,i) = 1.0;
107  }
108 
109  double *p_balancing_mat = balancing_mat.fortran_vec ();
110  double *p_balancing_mat2 = balancing_mat2.fortran_vec ();
111 
112  // first left
113  F77_XFCN (dggbak, DGGBAK, (F77_CONST_CHAR_ARG2 (&job, 1),
114  F77_CONST_CHAR_ARG2 ("L", 1),
115  n, ilo, ihi, plscale, prscale,
116  n, p_balancing_mat, n, info
117  F77_CHAR_ARG_LEN (1)
118  F77_CHAR_ARG_LEN (1)));
119 
120  // then right
121  F77_XFCN (dggbak, DGGBAK, (F77_CONST_CHAR_ARG2 (&job, 1),
122  F77_CONST_CHAR_ARG2 ("R", 1),
123  n, ilo, ihi, plscale, prscale,
124  n, p_balancing_mat2, n, info
125  F77_CHAR_ARG_LEN (1)
126  F77_CHAR_ARG_LEN (1)));
127 
128  return info;
129 }