1 /* 2 3 Copyright (C) 2009-2016 Lukas F. Reichlin 4 5 This file is part of LTI Syncope. 6 7 LTI Syncope is free software: you can redistribute it and/or modify 8 it under the terms of the GNU General Public License as published by 9 the Free Software Foundation, either version 3 of the License, or 10 (at your option) any later version. 11 12 LTI Syncope is distributed in the hope that it will be useful, 13 but WITHOUT ANY WARRANTY; without even the implied warranty of 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 GNU General Public License for more details. 16 17 You should have received a copy of the GNU General Public License 18 along with LTI Syncope. If not, see <http://www.gnu.org/licenses/>. 19 20 Hankel singular values. 21 Uses SLICOT AB13AD by courtesy of NICONET e.V. 22 <http://www.slicot.org> 23 24 Author: Lukas Reichlin <lukas.reichlin@gmail.com> 25 Created: January 2010 26 Version: 0.4 27 28 */ 29 30 #include <octave/oct.h> 31 #include "common.h" 32 33 extern "C" 34 { 35 int F77_FUNC (ab13ad, AB13AD) 36 (char& DICO, char& EQUIL, 37 F77_INT& N, F77_INT& M, F77_INT& P, 38 double& ALPHA, 39 double* A, F77_INT& LDA, 40 double* B, F77_INT& LDB, 41 double* C, F77_INT& LDC, 42 F77_INT& NS, 43 double* HSV, 44 double* DWORK, F77_INT& LDWORK, 45 F77_INT& INFO); 46 } 47 48 // PKG_ADD: autoload ("__sl_ab13ad__", "__control_slicot_functions__.oct"); 49 DEFUN_DLD (__sl_ab13ad__, args, nargout, 50 "-*- texinfo -*-\n\ 51 Slicot AB13AD Release 5.0\n\ 52 No argument checking.\n\ 53 For internal use only.") 54 { 55 octave_idx_type nargin = args.length (); 56 octave_value_list retval; 57 58 if (nargin != 6) 59 { 60 print_usage (); 61 } 62 else 63 { 64 // arguments in 65 char dico; 66 char equil; 67 68 Matrix a = args(0).matrix_value (); 69 Matrix b = args(1).matrix_value (); 70 Matrix c = args(2).matrix_value (); 71 F77_INT discrete = args(3).int_value (); 72 double alpha = args(4).double_value (); 73 const F77_INT scaled = args(5).int_value (); 74 75 if (discrete == 0) 76 dico = 'C'; 77 else 78 dico = 'D'; 79 80 if (scaled == 0) 81 equil = 'S'; 82 else 83 equil = 'N'; 84 85 86 F77_INT n = TO_F77_INT (a.rows ()); // n: number of states 87 F77_INT m = TO_F77_INT (b.columns ()); // m: number of inputs 88 F77_INT p = TO_F77_INT (c.rows ()); // p: number of outputs 89 90 F77_INT lda = max (1, TO_F77_INT (a.rows ())); 91 F77_INT ldb = max (1, TO_F77_INT (b.rows ())); 92 F77_INT ldc = max (1, TO_F77_INT (c.rows ())); 93 94 // arguments out 95 F77_INT ns = 0; 96 97 ColumnVector hsv (n); 98 99 // workspace 100 F77_INT ldwork = max (1, n*(max (n, m, p) + 5) + n*(n+1)/2); 101 102 OCTAVE_LOCAL_BUFFER (double, dwork, ldwork); 103 104 // error indicators 105 F77_INT info = 0; 106 107 108 // SLICOT routine AB13AD 109 F77_XFCN (ab13ad, AB13AD, 110 (dico, equil, 111 n, m, p, 112 alpha, 113 a.fortran_vec (), lda, 114 b.fortran_vec (), ldb, 115 c.fortran_vec (), ldc, 116 ns, 117 hsv.fortran_vec (), 118 dwork, ldwork, 119 info)); 120 121 if (f77_exception_encountered) 122 error ("hsvd: __sl_ab13ad__: exception in SLICOT subroutine AB13AD"); 123 124 if (info != 0) 125 error ("hsvd: __sl_ab13ad__: AB13AD returned info = %d", static_cast<int> (info)); 126 127 // resize 128 hsv.resize (ns); 129 130 // return values 131 retval(0) = hsv; 132 retval(1) = octave_value (ns); 133 } 134 135 return retval; 136 } 137