Mercurial > octave-antonio
view scripts/linear-algebra/istril.m @ 19833:9fc020886ae9
maint: Clean up m-files to follow Octave coding conventions.
Try to trim long lines to < 80 chars.
Use '##' for single line comments.
Use '(...)' around tests for if/elseif/switch/while.
Abut cell indexing operator '{' next to variable.
Abut array indexing operator '(' next to variable.
Use space between negation operator '!' and following expression.
Use two newlines between endfunction and start of %!test or %!demo code.
Remove unnecessary parens grouping between short-circuit operators.
Remove stray extra spaces (typos) between variables and assignment operators.
Remove stray extra spaces from ends of lines.
author | Rik <rik@octave.org> |
---|---|
date | Mon, 23 Feb 2015 14:54:39 -0800 |
parents | 4197fc428c7d |
children | 03b9d17a2d95 |
line wrap: on
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## Copyright (C) 2014-2015 Massimiliano Fasi ## ## 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 ## <http://www.gnu.org/licenses/>. ## -*- texinfo -*- ## @deftypefn {Function File} {} istril (@var{A}) ## Return true if @var{A} is a lower triangular matrix. ## ## A lower triangular matrix has nonzero entries only on the main diagonal ## and below. ## @seealso{istriu, isbanded, isdiag, tril, bandwidth} ## @end deftypefn ## Author: Massimiliano Fasi function retval = istril (A) if (nargin != 1) print_usage (); endif retval = (isnumeric (A) || islogical (A)) && ndims (A) == 2; if (retval) [i, j] = find (A); retval = all (i >= j); endif endfunction %!assert (! istril ("string")) %!assert (istril ([])) %!assert (! istril (zeros (2,2,2))) %!assert (istril (1)) %!assert (! istril ([1, 1])) %!assert (istril ([1; 1])) %!assert (istril (eye (10))) %!assert (istril (speye (100))) %!assert (istril (tril (randn (10)))) %!assert (! istril (randn (10))) ## Test input validation %!error istril () %!error istril (1,2)