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2928
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1 /* |
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2 |
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3 Copyright (C) 1996, 1997 John W. Eaton |
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4 |
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5 This file is part of Octave. |
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6 |
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7 Octave is free software; you can redistribute it and/or modify it |
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8 under the terms of the GNU General Public License as published by the |
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9 Free Software Foundation; either version 2, or (at your option) any |
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10 later version. |
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11 |
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12 Octave is distributed in the hope that it will be useful, but WITHOUT |
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13 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
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14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
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15 for more details. |
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16 |
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17 You should have received a copy of the GNU General Public License |
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18 along with Octave; see the file COPYING. If not, write to the Free |
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19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
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20 |
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21 */ |
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22 |
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23 #ifdef HAVE_CONFIG_H |
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24 #include <config.h> |
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25 #endif |
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26 |
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27 #include "CmplxDET.h" |
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28 #include "dbleDET.h" |
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29 |
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30 #include "defun-dld.h" |
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31 #include "error.h" |
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32 #include "gripes.h" |
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33 #include "oct-obj.h" |
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34 #include "utils.h" |
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35 |
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3808
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36 DEFUN_DLD (det, args, nargout, |
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37 "-*- texinfo -*-\n\ |
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3808
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38 @deftypefn {Loadable Function} {[@var{d}, @var{rcond}] = } det (@var{a})\n\ |
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39 Compute the determinant of @var{a} using @sc{Lapack}. Return an estimate\n\ |
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40 of the reciprocal condition number if requested.\n\ |
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41 @end deftypefn") |
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42 { |
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43 octave_value_list retval; |
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44 |
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45 int nargin = args.length (); |
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46 |
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47 if (nargin != 1) |
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48 { |
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49 print_usage ("det"); |
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50 return retval; |
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51 } |
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52 |
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53 octave_value arg = args(0); |
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54 |
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55 int nr = arg.rows (); |
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56 int nc = arg.columns (); |
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57 |
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58 if (nr == 0 && nc == 0) |
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59 { |
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4233
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60 retval(0) = 1.0; |
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61 return retval; |
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62 } |
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63 |
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64 int arg_is_empty = empty_arg ("det", nr, nc); |
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65 if (arg_is_empty < 0) |
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66 return retval; |
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67 if (arg_is_empty > 0) |
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4233
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68 return octave_value (Matrix (1, 1, 1.0)); |
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69 |
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70 if (nr != nc) |
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71 { |
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72 gripe_square_matrix_required ("det"); |
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73 return retval; |
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74 } |
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75 |
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76 if (arg.is_real_type ()) |
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77 { |
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78 Matrix m = arg.matrix_value (); |
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79 |
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80 if (! error_state) |
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81 { |
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5070
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82 // Always compute rcond, so we can detect numerically |
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83 // singular matrices. |
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84 |
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85 int info; |
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86 double rcond = 0.0; |
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87 DET det = m.determinant (info, rcond); |
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88 retval(1) = rcond; |
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89 volatile double xrcond = rcond; |
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90 xrcond += 1.0; |
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91 retval(0) = ((info == -1 || xrcond == 1.0) ? 0.0 : det.value ()); |
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92 } |
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93 } |
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94 else if (arg.is_complex_type ()) |
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95 { |
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96 ComplexMatrix m = arg.complex_matrix_value (); |
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97 |
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98 if (! error_state) |
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99 { |
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5070
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100 // Always compute rcond, so we can detect numerically |
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101 // singular matrices. |
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102 |
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103 int info; |
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104 double rcond = 0.0; |
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105 ComplexDET det = m.determinant (info, rcond); |
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106 retval(1) = rcond; |
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107 volatile double xrcond = rcond; |
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108 xrcond += 1.0; |
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109 retval(0) = ((info == -1 || xrcond == 1.0) |
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110 ? Complex (0.0) : det.value ()); |
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111 } |
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112 } |
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113 else |
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114 { |
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115 gripe_wrong_type_arg ("det", arg); |
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116 } |
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117 |
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118 return retval; |
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119 } |
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120 |
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121 /* |
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122 ;;; Local Variables: *** |
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123 ;;; mode: C++ *** |
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124 ;;; End: *** |
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125 */ |
