Mercurial > octave
view scripts/general/sortrows.m @ 30564:796f54d4ddbf stable
update Octave Project Developers copyright for the new year
In files that have the "Octave Project Developers" copyright notice,
update for 2021.
In all .txi and .texi files except gpl.txi and gpl.texi in the
doc/liboctave and doc/interpreter directories, change the copyright
to "Octave Project Developers", the same as used for other source
files. Update copyright notices for 2022 (not done since 2019). For
gpl.txi and gpl.texi, change the copyright notice to be "Free Software
Foundation, Inc." and leave the date at 2007 only because this file
only contains the text of the GPL, not anything created by the Octave
Project Developers.
Add Paul Thomas to contributors.in.
author | John W. Eaton <jwe@octave.org> |
---|---|
date | Tue, 28 Dec 2021 18:22:40 -0500 |
parents | 7854d5752dd2 |
children | 597f3ee61a48 |
line wrap: on
line source
######################################################################## ## ## Copyright (C) 2000-2022 The Octave Project Developers ## ## See the file COPYRIGHT.md in the top-level directory of this ## distribution or <https://octave.org/copyright/>. ## ## This file is part of Octave. ## ## 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 3 of the License, 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 Octave; see the file COPYING. If not, see ## <https://www.gnu.org/licenses/>. ## ######################################################################## ## -*- texinfo -*- ## @deftypefn {} {[@var{s}, @var{i}] =} sortrows (@var{A}) ## @deftypefnx {} {[@var{s}, @var{i}] =} sortrows (@var{A}, @var{c}) ## Sort the rows of the matrix @var{A} according to the order of the columns ## specified in @var{c}. ## ## By default (@var{c} omitted, or a particular column unspecified in @var{c}) ## an ascending sort order is used. However, if elements of @var{c} are ## negative then the corresponding column is sorted in descending order. If ## the elements of @var{A} are strings then a lexicographical sort is used. ## ## Example: sort by column 2 in descending order, then 3 in ascending order ## ## @example ## @group ## x = [ 7, 1, 4; ## 8, 3, 5; ## 9, 3, 6 ]; ## sortrows (x, [-2, 3]) ## @result{} 8 3 5 ## 9 3 6 ## 7 1 4 ## @end group ## @end example ## ## @seealso{sort} ## @end deftypefn function [s, i] = sortrows (A, c) if (nargin < 1) print_usage (); endif if (nargin == 2) if (! (isnumeric (c) && isvector (c))) error ("sortrows: C must be a numeric vector"); elseif (any (c == 0) || any (abs (c) > columns (A))) error ("sortrows: all elements of C must be in the range [1, columns (A)]"); endif endif default_mode = "ascend"; reverse_mode = "descend"; if (issparse (A) || iscell (A)) ## FIXME: Eliminate this case once __sort_rows_idx__ is fixed to ## handle sparse matrices. if (nargin == 1) i = sort_rows_idx_generic (default_mode, reverse_mode, A); else i = sort_rows_idx_generic (default_mode, reverse_mode, A, c); endif elseif (nargin == 1) i = __sort_rows_idx__ (A, default_mode); elseif (all (c > 0)) i = __sort_rows_idx__ (A(:,c), default_mode); elseif (all (c < 0)) i = __sort_rows_idx__ (A(:,-c), reverse_mode); else ## Otherwise, fall back to the old algorithm. i = sort_rows_idx_generic (default_mode, reverse_mode, A, c); endif ## Only bother to compute s if needed. if (isargout (1)) s = A(i,:); endif endfunction function i = sort_rows_idx_generic (default_mode, reverse_mode, m, c) if (nargin == 3) indices = [1:columns(m)]'; mode(1:columns(m)) = {default_mode}; else for j = 1:length (c) if (c(j) < 0) mode{j} = reverse_mode; else mode{j} = default_mode; endif endfor indices = abs (c(:)); endif ## Since sort is 'stable' the order of identical elements will be ## preserved, so by traversing the sort indices in reverse order we ## will make sure that identical elements in index i are subsorted by ## index j. indices = flipud (indices); mode = flipud (mode'); i = [1:rows(m)]'; for j = 1:length (indices) M = m(i, indices(j)); if (iscell (M) && ! iscellstr (M)) M = cell2mat (M); endif [~, idx] = sort (M, mode{j}); i = i(idx); endfor endfunction %!test %! m = [1, 1; 1, 2; 3, 6; 2, 7]; %! c = [1, -2]; %! [x, idx] = sortrows (m, c); %! [sx, sidx] = sortrows (sparse (m), c); %! assert (x, [1, 2; 1, 1; 2, 7; 3, 6]); %! assert (idx, [2; 1; 4; 3]); %! assert (issparse (sx)); %! assert (x, full (sx)); %! assert (idx, sidx); %!test %! m = [1, 0, 0, 4]; %! c = 1; %! [x, idx] = sortrows (m, c); %! [sx, sidx] = sortrows (sparse (m), c); %! assert (x, m); %! assert (idx, 1); %! assert (issparse (sx)); %! assert (x, full (sx)); %! assert (idx, sidx); %!test <*42523> %! C = {1, 2, "filename1"; %! 3, 4, "filename2"; %! 5, 6, "filename3"}; %! C2 = sortrows (C, -1); %! assert (C2, flipud (C)); ## Test input validation %!error <Invalid call> sortrows () %!error sortrows (1, "ascend") %!error sortrows (1, ones (2,2)) %!error sortrows (1, 0) %!error sortrows (1, 2)