Mercurial > octave
view scripts/linear-algebra/istriu.m @ 30239:120e878f343f
mkdir.m: issue a warning if DIR already exists (bug #61338)
* mkdir.m: When nargout==0, check status message and report a warning if
"directory exists" message found.
author | Rik <rik@octave.org> |
---|---|
date | Wed, 13 Oct 2021 08:05:14 -0700 |
parents | 7854d5752dd2 |
children | 83aeaba707d8 796f54d4ddbf |
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######################################################################## ## ## Copyright (C) 2014-2021 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 {} {} istriu (@var{A}) ## Return true if @var{A} is an upper triangular matrix. ## ## An upper triangular matrix has nonzero entries only on the main diagonal and ## above. ## @seealso{isdiag, isbanded, istril, triu, bandwidth} ## @end deftypefn function retval = istriu (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 (! istriu ("string")) %!assert (istriu ([])) %!assert (! istriu (zeros (2,2,2))) %!assert (istriu (1)) %!assert (istriu ([1, 1])) %!assert (! istriu ([1; 1])) %!assert (istriu (eye (10))) %!assert (istriu (speye (100))) %!assert (istriu (triu (randn (10)))) %!assert (! istriu (randn (10))) ## Test input validation %!error <Invalid call> istriu ()