Mercurial > hg > octave-lyh
changeset 6011:d3112590883f
[project @ 2006-09-29 18:20:08 by jwe]
author | jwe |
---|---|
date | Fri, 29 Sep 2006 18:20:15 +0000 |
parents | 5e4d1e774641 |
children | 7c048a800ebe |
files | src/ChangeLog src/DLD-FUNCTIONS/spfind.cc src/Makefile.in |
diffstat | 3 files changed, 291 insertions(+), 1 deletions(-) [+] |
line wrap: on
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--- a/src/ChangeLog +++ b/src/ChangeLog @@ -4,6 +4,8 @@ (OCTAVE_API_VERSION): Now api-v22. (OCTAVE_RELEASE_DATE): Now 2006-09-29. + * Makefile.in (DEP_5): Include oct-errno.cc in the list. + 2006-09-27 John W. Eaton <jwe@octave.org> * pr-output.cc (abs): New template function. Instantiate for
new file mode 100644 --- /dev/null +++ b/src/DLD-FUNCTIONS/spfind.cc @@ -0,0 +1,288 @@ +/* + +Copyright (C) 2006 David Bateman + +Octave is free software; you can redistribute it and/or modify it +under the terms of the GNU General Public License as published by the +Free Software Foundation; either version 2, or (at your option) any +later version. + +Octave is distributed in the hope that it will be useful, but WITHOUT +ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or +FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License +for more details. + +You should have received a copy of the GNU General Public License +along with this program; see the file COPYING. If not, write to the +Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, +Boston, MA 02110-1301, USA. + +*/ + +#ifdef HAVE_CONFIG_H +#include <config.h> +#endif + +#include <cstdlib> +#include <string> + +#include "variables.h" +#include "utils.h" +#include "pager.h" +#include "defun-dld.h" +#include "gripes.h" +#include "quit.h" + +#include "ov-re-sparse.h" +#include "ov-cx-sparse.h" + +template <typename T, typename M> +octave_value_list +sparse_find_non_zero_elem_idx (const T& v, M& val, int nargout, + octave_idx_type n_to_find, int direction) +{ + octave_value_list retval ((nargout == 0 ? 1 : nargout), Matrix ()); + + + octave_idx_type nc = v.cols(); + octave_idx_type nr = v.rows(); + octave_idx_type nz = v.nnz(); + + // Search in the default range. + octave_idx_type start_nc = -1; + octave_idx_type end_nc = -1; + octave_idx_type count; + + // Search for the range to search + if (n_to_find < 0) + { + start_nc = 0; + end_nc = nc; + n_to_find = nz; + count = nz; + } + else if (direction > 0) + { + for (octave_idx_type j = 0; j < nc; j++) + { + OCTAVE_QUIT; + if (v.cidx(j) == 0 && v.cidx(j+1) != 0) + start_nc = j; + if (v.cidx(j+1) >= n_to_find) + { + end_nc = j + 1; + break; + } + } + } + else + { + for (octave_idx_type j = nc; j > 0; j--) + { + OCTAVE_QUIT; + if (v.cidx(j) == nz && v.cidx(j-1) != nz) + end_nc = j; + if (nz - v.cidx(j-1) >= n_to_find) + { + start_nc = j - 1; + break; + } + } + } + + count = (n_to_find > v.cidx(end_nc) - v.cidx(start_nc) ? + v.cidx(end_nc) - v.cidx(start_nc) : n_to_find); + + // If the original argument was a row vector, force a row vector of + // the overall indices to be returned. But see below for scalar + // case... + + octave_idx_type result_nr = count; + octave_idx_type result_nc = 1; + + bool scalar_arg = false; + + if (v.rows () == 1) + { + result_nr = 1; + result_nc = count; + + scalar_arg = (v.columns () == 1); + } + + Matrix idx (result_nr, result_nc); + + Matrix i_idx (result_nr, result_nc); + Matrix j_idx (result_nr, result_nc); + + val = M(result_nr, result_nc); + + if (count > 0) + { + // Search for elements to return. Only search the region where + // there are elements to be found using the count that we want + // to find. + for (octave_idx_type j = start_nc, cx = 0; j < end_nc; j++) + for (octave_idx_type i = v.cidx(j); i < v.cidx(j+1); i++ ) + { + OCTAVE_QUIT; + if (direction < 0 && i < nz - count) + continue; + i_idx (cx) = static_cast<double> (v.ridx(i) + 1); + j_idx (cx) = static_cast<double> (j + 1); + idx (cx) = j * nc + v.ridx(i) + 1; + val (cx) = v.data(i); + cx++; + if (cx == count) + break; + } + } + else if (scalar_arg) + { + idx.resize (0, 0); + + i_idx.resize (0, 0); + j_idx.resize (0, 0); + + val.resize (0, 0); + } + + switch (nargout) + { + case 0: + case 1: + retval(0) = idx; + break; + + case 5: + retval(4) = nc; + // Fall through + + case 4: + retval(3) = nr; + // Fall through + + case 3: + retval(2) = val; + // Fall through! + + case 2: + retval(1) = j_idx; + retval(0) = i_idx; + break; + + default: + panic_impossible (); + break; + } + + return retval; +} + +template octave_value_list sparse_find_non_zero_elem_idx + (const SparseMatrix&, Matrix&, int, octave_idx_type, int); + +template octave_value_list sparse_find_non_zero_elem_idx + (const SparseComplexMatrix&, ComplexMatrix&, int, octave_idx_type, int); + + +// PKG_ADD: dispatch ("find", "spfind", "sparse matrix"); +// PKG_ADD: dispatch ("find", "spfind", "sparse complex matrix"); +// PKG_ADD: dispatch ("find", "spfind", "sparse bool matrix"); +DEFUN_DLD (spfind, args, nargout, + "-*- texinfo -*-\n\ +@deftypefn {Loadable Function} {} spfind (@var{x})\n\ +@deftypefnx {Loadable Function} {} spfind (@var{x}, @var{n})\n\ +@deftypefnx {Loadable Function} {} spfind (@var{x}, @var{n}, @var{direction})\n\ +@deftypefnx {Loadable Function} {[@var{i}, @var{j}, @var{v}} spfind (@dots{})\n\ +\n\ +A sparse version of the @code{find} function. Please see the @code{find}\n\ +for details of its use.\n\ +\n\ +Note that this function is particularly useful for sparse matrices, as\n\ +it extracts the non-zero elements as vectors, which can then be used to\n\ +create the original matrix. For example,\n\ +\n\ +@example\n\ +@group\n\ +sz = size(a);\n\ +[i, j, v] = spfind (a);\n\ +b = sparse(i, j, v, sz(1), sz(2));\n\ +@end group\n\ +@end example\n\ +@seealso{sparse}\n\ +@end deftypefn") +{ + octave_value_list retval; + int nargin = args.length (); + + if (nargin > 3 || nargin < 1) + { + print_usage (); + return retval; + } + + // Setup the default options. + octave_idx_type n_to_find = -1; + if (nargin > 1) + { + n_to_find = args(1).int_value (); + if (error_state) + { + error ("find: expecting second argument to be an integer"); + return retval; + } + } + + // Direction to do the searching (1 == forward, -1 == reverse). + int direction = 1; + if (nargin > 2) + { + direction = 0; + + std::string s_arg = args(2).string_value (); + + if (! error_state) + { + if (s_arg == "first") + direction = 1; + else if (s_arg == "last") + direction = -1; + } + + if (direction == 0) + { + error ("find: expecting third argument to be \"first\" or \"last\""); + return retval; + } + } + + octave_value arg = args(0); + + if (arg.is_real_type ()) + { + SparseMatrix v = arg.sparse_matrix_value (); + Matrix val; + + if (! error_state) + retval = sparse_find_non_zero_elem_idx (v, val, nargout, n_to_find, direction); + } + else if (arg.is_complex_type ()) + { + SparseComplexMatrix v = arg.sparse_complex_matrix_value (); + ComplexMatrix val; + + if (! error_state) + retval = sparse_find_non_zero_elem_idx (v, val, nargout, n_to_find, direction); + } + else + gripe_wrong_type_arg ("spfind", arg); + + return retval; +} + +/* +;;; Local Variables: *** +;;; mode: C++ *** +;;; End: *** +*/
--- a/src/Makefile.in +++ b/src/Makefile.in @@ -204,7 +204,7 @@ # Ugh. -DEP_5 := $(SOURCES) $(DLD_SRC) builtins.cc ops.cc main.c +DEP_5 := $(SOURCES) $(DLD_SRC) builtins.cc oct-errno.cc ops.cc main.c DEP_4 := $(notdir $(DEP_5)) DEP_3 := $(patsubst %.l, %.cc, $(DEP_4)) DEP_2 := $(patsubst %.y, %.cc, $(DEP_3))