Mercurial > octave
view scripts/set/powerset.m @ 31253:a40c0b7aa376
maint: changes to follow Octave coding conventions.
* NEWS.8.md: Wrap lines to 72 chars.
* LSODE-opts.in: Use two spaces after sentence ending period.
* LSODE.cc: Use minimum of two spaces between code and start of comment.
* MemoizedFunction.m: Change copyright date to 2022 since this is the year it
was accepted into core. Don't wrap error() lines to 80 chars. Use newlines
to improve readability of switch statements. Use minimum of two spaces between
code and start of comment.
* del2.m, integral.m, interp1.m, interp2.m, griddata.m, inpolygon.m, waitbar.m,
cubehelix.m, ind2x.m, importdata.m, textread.m, logm.m, lighting.m, shading.m,
xticklabels.m, yticklabels.m, zticklabels.m, colorbar.m, meshc.m, print.m,
__gnuplot_draw_axes__.m, struct2hdl.m, ppval.m, ismember.m, iqr.m: Use a space
between comment character '#' and start of comment. Use hyphen for adjectives
describing dimensions such as "1-D".
* vectorize.m, ode23s.m: Use is_function_handle() instead of "isa (x, "function_handle")"
for clarity and performance.
* clearAllMemoizedCaches.m: Change copyright date to 2022 since this is the
year it was accepted into core. Remove input validation which is done by
interpreter. Use two newlines between end of code and start of BIST tests.
* memoize.m: Change copyright date to 2022 since this is the year it was
accepted into core. Re-wrap documentation to 80 chars. Use
is_function_handle() instead of "isa (x, "function_handle")" for clarity and
performance. Use two newlines between end of code and start of BIST tests.
Use semicolon for assert statements within %!test block. Re-write BIST tests
for input validation.
* __memoize__.m: Change copyright date to 2022 since this is the year it was
accepted into core. Use spaces in for statements to improve readability.
* unique.m: Add FIXME note to commented BIST test
* dec2bin.m: Remove stray newline at end of file.
* triplequad.m: Reduce doubly-commented BIST syntax using "#%!#" to "#%!".
* delaunayn.m: Use input variable names in error() statements. Use minimum of
two spaces between code and start of comment. Use hyphen for describing
dimensions. Use two newlines between end of code and start of BIST tests.
Update BIST tests to pass.
author | Rik <rik@octave.org> |
---|---|
date | Mon, 03 Oct 2022 18:06:55 -0700 |
parents | 5d3faba0342e |
children | 597f3ee61a48 |
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######################################################################## ## ## Copyright (C) 2010-2022 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{p} =} powerset (@var{a}) ## @deftypefnx {} {@var{p} =} powerset (@var{a}, "rows") ## Compute the powerset (all subsets) of the set @var{a}. ## ## The set @var{a} must be a numerical matrix or a cell array of strings. The ## output will always be a cell array of either vectors or strings. ## ## With the optional argument @qcode{"rows"}, each row of the set @var{a} is ## considered one element of the set. The input must be a 2-D numeric matrix ## to use this argument. ## ## @seealso{unique, union, intersect, setdiff, setxor, ismember} ## @end deftypefn function p = powerset (a, byrows_arg) if (nargin < 1) print_usage (); endif byrows = false; if (nargin == 2) if (! strcmpi (byrows_arg, "rows")) error ('powerset: optional second argument must be "rows"'); elseif (iscell (a)) error ('powerset: "rows" not valid for cell arrays'); else byrows = true; endif endif if (iscell (a) && ! iscellstr (a)) error ("powerset: cell arrays can only be used for character strings"); endif if (byrows) a = unique (a, "rows"); n = rows (a); else a = unique (a); n = numel (a); endif if (n == 0) p = {}; else if (n > 32) error ("powerset: not implemented for more than 32 elements"); endif ## Logical rep m = uint32 (0:2^n-1); ## FIXME: better test for endianness? if (bitunpack (uint16 (1))(1) == 0) m = swapbytes (m); endif b = reshape (bitunpack (m), 32, 2^n)(1:n,:); ## Convert to indices and lengths. [i, k] = find (b); k = sum (b, 1); ## Index and split. if (byrows) p = mat2cell (a(i,:), k, columns (a)); else if (rows (a) == 1) p = mat2cell (a(i), 1, k); else p = mat2cell (a(i), k, 1); endif endif endif endfunction %!test %! c = sort (cellstr ({[], [1], [2], [3], [1, 2], [1, 3], [2, 3], [1, 2, 3]})); %! p = sort (cellstr (powerset ([1, 2, 3]))); %! assert (p, c); %!test %! c = sort (cellstr ({ [], [1:3], [2:4], [3:5], [1:3; 2:4], [1:3; 3:5], [2:4; 3:5], [1:3; 2:4; 3:5]})); %! p = sort (cellstr (powerset ([1:3;2:4;3:5], "rows"))); %! assert (p,c); %!assert (powerset([]), {}); # always return a cell array ## Test input validation %!error <Invalid call> powerset () %!error <second argument must be "rows"> powerset (1, "cols") %!error <"rows" not valid for cell arrays> powerset ({1}, "rows") %!error <cell arrays can only be used for character> powerset ({1}) %!error <not implemented for more than 32 elements> powerset (1:33)