|
515
|
1 // f-find.cc -*- C++ -*- |
|
|
2 /* |
|
|
3 |
|
1009
|
4 Copyright (C) 1994, 1995 John W. Eaton |
|
515
|
5 |
|
|
6 This file is part of Octave. |
|
|
7 |
|
|
8 Octave is free software; you can redistribute it and/or modify it |
|
|
9 under the terms of the GNU General Public License as published by the |
|
|
10 Free Software Foundation; either version 2, or (at your option) any |
|
|
11 later version. |
|
|
12 |
|
|
13 Octave is distributed in the hope that it will be useful, but WITHOUT |
|
|
14 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
|
|
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
|
|
16 for more details. |
|
|
17 |
|
|
18 You should have received a copy of the GNU General Public License |
|
|
19 along with Octave; see the file COPYING. If not, write to the Free |
|
1315
|
20 Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
|
515
|
21 |
|
|
22 */ |
|
|
23 |
|
|
24 #ifdef HAVE_CONFIG_H |
|
1192
|
25 #include <config.h> |
|
515
|
26 #endif |
|
|
27 |
|
|
28 #include "tree-const.h" |
|
|
29 #include "error.h" |
|
778
|
30 #include "gripes.h" |
|
544
|
31 #include "help.h" |
|
519
|
32 #include "defun-dld.h" |
|
515
|
33 |
|
|
34 static Octave_object |
|
|
35 find_to_fortran_idx (const ColumnVector i_idx, const ColumnVector j_idx, |
|
|
36 const tree_constant& val, int nr, int nc, int nargout) |
|
|
37 { |
|
565
|
38 Octave_object retval; |
|
515
|
39 |
|
|
40 switch (nargout) |
|
|
41 { |
|
636
|
42 case 0: |
|
515
|
43 case 1: |
|
|
44 { |
|
|
45 int count = i_idx.length (); |
|
|
46 ColumnVector tmp (count); |
|
|
47 for (int i = 0; i < count; i++) |
|
|
48 tmp (i) = nr * (j_idx (i) - 1.0) + i_idx (i); |
|
1020
|
49 |
|
|
50 // If the original argument was a row vector, force a row vector of |
|
|
51 // indices to be returned. |
|
|
52 |
|
|
53 retval(0) = tree_constant (tmp, (nr != 1)); |
|
515
|
54 } |
|
|
55 break; |
|
636
|
56 |
|
515
|
57 case 3: |
|
|
58 retval(2) = val; |
|
636
|
59 // Fall through! |
|
|
60 |
|
515
|
61 case 2: |
|
636
|
62 retval(1) = tree_constant (j_idx, 1); |
|
515
|
63 retval(0) = tree_constant (i_idx, 1); |
|
|
64 // If you want this to work more like Matlab, use the following line |
|
|
65 // instead of the previous one. |
|
|
66 // retval(0) = tree_constant (i_idx, (nr != 1)); |
|
|
67 break; |
|
636
|
68 |
|
515
|
69 default: |
|
|
70 panic_impossible (); |
|
|
71 break; |
|
|
72 } |
|
|
73 |
|
|
74 return retval; |
|
|
75 } |
|
|
76 |
|
|
77 static Octave_object |
|
|
78 find_nonzero_elem_idx (const Matrix& m, int nargout) |
|
|
79 { |
|
|
80 int count = 0; |
|
|
81 int m_nr = m.rows (); |
|
|
82 int m_nc = m.columns (); |
|
|
83 |
|
|
84 int i, j; |
|
|
85 for (j = 0; j < m_nc; j++) |
|
|
86 for (i = 0; i < m_nr; i++) |
|
|
87 if (m.elem (i, j) != 0.0) |
|
|
88 count++; |
|
|
89 |
|
636
|
90 Octave_object retval (((nargout == 0) ? 1 : nargout), Matrix ()); |
|
515
|
91 |
|
|
92 if (count == 0) |
|
|
93 return retval; |
|
|
94 |
|
|
95 ColumnVector i_idx (count); |
|
|
96 ColumnVector j_idx (count); |
|
|
97 ColumnVector v (count); |
|
|
98 |
|
|
99 count = 0; |
|
|
100 for (j = 0; j < m_nc; j++) |
|
|
101 for (i = 0; i < m_nr; i++) |
|
|
102 { |
|
|
103 double d = m.elem (i, j); |
|
|
104 if (d != 0.0) |
|
|
105 { |
|
|
106 i_idx (count) = i + 1; |
|
|
107 j_idx (count) = j + 1; |
|
|
108 v (count) = d; |
|
|
109 count++; |
|
|
110 } |
|
|
111 } |
|
|
112 |
|
|
113 tree_constant tmp (v, 1); |
|
|
114 return find_to_fortran_idx (i_idx, j_idx, tmp, m_nr, m_nc, nargout); |
|
|
115 } |
|
|
116 |
|
|
117 static Octave_object |
|
|
118 find_nonzero_elem_idx (const ComplexMatrix& m, int nargout) |
|
|
119 { |
|
|
120 int count = 0; |
|
|
121 int m_nr = m.rows (); |
|
|
122 int m_nc = m.columns (); |
|
|
123 |
|
|
124 int i, j; |
|
|
125 for (j = 0; j < m_nc; j++) |
|
|
126 for (i = 0; i < m_nr; i++) |
|
|
127 if (m.elem (i, j) != 0.0) |
|
|
128 count++; |
|
|
129 |
|
636
|
130 Octave_object retval (((nargout == 0) ? 1 : nargout), Matrix ()); |
|
515
|
131 |
|
|
132 if (count == 0) |
|
|
133 return retval; |
|
|
134 |
|
|
135 ColumnVector i_idx (count); |
|
|
136 ColumnVector j_idx (count); |
|
|
137 ComplexColumnVector v (count); |
|
|
138 |
|
|
139 count = 0; |
|
|
140 for (j = 0; j < m_nc; j++) |
|
|
141 for (i = 0; i < m_nr; i++) |
|
|
142 { |
|
|
143 Complex c = m.elem (i, j); |
|
|
144 if (c != 0.0) |
|
|
145 { |
|
1094
|
146 i_idx (count) = i + 1; |
|
|
147 j_idx (count) = j + 1; |
|
515
|
148 v (count) = c; |
|
|
149 count++; |
|
|
150 } |
|
|
151 } |
|
|
152 |
|
|
153 tree_constant tmp (v, 1); |
|
|
154 return find_to_fortran_idx (i_idx, j_idx, tmp, m_nr, m_nc, nargout); |
|
|
155 } |
|
|
156 |
|
701
|
157 DEFUN_DLD_BUILTIN ("find", Ffind, Sfind, 2, 3, |
|
519
|
158 "find (X) or [I, J, V] = find (X): Return indices of nonzero elements") |
|
515
|
159 { |
|
519
|
160 Octave_object retval; |
|
|
161 |
|
|
162 int nargin = args.length (); |
|
|
163 |
|
712
|
164 if (nargin != 1 || nargout > 3) |
|
519
|
165 { |
|
|
166 print_usage ("find"); |
|
|
167 return retval; |
|
|
168 } |
|
515
|
169 |
|
712
|
170 tree_constant arg = args(0); |
|
515
|
171 |
|
636
|
172 if (arg.is_real_type ()) |
|
620
|
173 { |
|
636
|
174 Matrix m = arg.matrix_value (); |
|
|
175 |
|
|
176 if (! error_state) |
|
|
177 retval = find_nonzero_elem_idx (m, nargout); |
|
620
|
178 } |
|
636
|
179 else if (arg.is_complex_type ()) |
|
515
|
180 { |
|
636
|
181 ComplexMatrix m = arg.complex_matrix_value (); |
|
|
182 |
|
|
183 if (! error_state) |
|
|
184 retval = find_nonzero_elem_idx (m, nargout); |
|
620
|
185 } |
|
|
186 else |
|
|
187 { |
|
636
|
188 gripe_wrong_type_arg ("find", arg); |
|
620
|
189 } |
|
|
190 |
|
515
|
191 return retval; |
|
|
192 } |
|
|
193 |
|
|
194 /* |
|
|
195 ;;; Local Variables: *** |
|
|
196 ;;; mode: C++ *** |
|
|
197 ;;; page-delimiter: "^/\\*" *** |
|
|
198 ;;; End: *** |
|
|
199 */ |
