Mercurial > octave
view scripts/special-matrix/wilkinson.m @ 27985:9f9ac219896d
maint: Remove remaining "Author:" instances from code base.
* __ftp__.cc, load-save.cc, urlwrite.cc, xnorm.cc, xnorm.h, cconv2.f,
cdotc3.f, cmatm3.f, csconv2.f, dconv2.f, ddot3.f, dmatm3.f, sconv2.f, sdot3.f,
smatm3.f, zconv2.f, zdconv2.f, zdotc3.f, zmatm3.f, crsf2csf.f, zrsf2csf.f,
oct-norm.cc, oct-norm.h, lin2mu.m, mu2lin.m, bincoeff.m, blkdiag.m, deal.m,
gradient.m, interpft.m, nextpow2.m, postpad.m, prepad.m, repmat.m, shift.m,
xor.m, griddata.m, rotx.m, roty.m, rotz.m, voronoin.m, getappdata.m,
isappdata.m, rmappdata.m, setappdata.m, colormap.m, gray.m, gray2ind.m,
im2double.m, image.m, imagesc.m, imread.m, imshow.m, ind2gray.m, ind2rgb.m,
ocean.m, __imread__.m, rgb2ind.m, javachk.m, ClassHelper.java, usejava.m,
findstr.m, commutation_matrix.m, cross.m, gls.m, housh.m, isdefinite.m,
ishermitian.m, issymmetric.m, logm.m, null.m, ols.m, orth.m, qzhess.m, rref.m,
dos.m, nargoutchk.m, orderfields.m, parseparams.m, __w2mpth__.m, unix.m,
untar.m, unzip.m, expand_rel_paths.m, make_rel_paths.m, daspect.m, orient.m,
pbaspect.m, rticks.m, thetaticks.m, xticklabels.m, xticks.m, yticklabels.m,
yticks.m, zticklabels.m, zticks.m, comet.m, contourf.m, plot3.m, cla.m,
copyobj.m, findfigs.m, hdl2struct.m, linkaxes.m, __ghostscript__.m,
__gnuplot_get_var__.m, __gnuplot_has_feature__.m, __gnuplot_has_terminal__.m,
__gnuplot_open_stream__.m, __gnuplot_print__.m, struct2hdl.m, subplot.m,
compan.m, conv.m, deconv.m, mpoles.m, poly.m, polyder.m, polyfit.m, polyint.m,
polyout.m, polyreduce.m, polyval.m, polyvalm.m, residue.m, roots.m, ismember.m,
__parse_movargs__.m, detrend.m, fftconv.m, fftfilt.m, fftshift.m, filter2.m,
movfun.m, movslice.m, ichol.m, pcg.m, beta.m, ellipke.m, lcm.m, nchoosek.m,
pow2.m, primes.m, pascal.m, rosser.m, wilkinson.m, corr.m, kurtosis.m,
skewness.m, base2dec.m, bin2dec.m, blanks.m, deblank.m, dec2base.m, dec2bin.m,
dec2hex.m, hex2dec.m, index.m, rindex.m, strjoin.m, substr.m, untabify.m,
calendar.m, datestr.m, eomday.m, now.m, weekday.m:
Remove remaining "Author:" instances from code base.
author | Rik <rik@octave.org> |
---|---|
date | Tue, 21 Jan 2020 14:35:03 -0800 |
parents | bd51beb6205e |
children | d8318c12d903 0a5b15007766 |
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######################################################################## ## ## Copyright (C) 1999-2020 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 {} {} wilkinson (@var{n}) ## Return the Wilkinson matrix of order @var{n}. ## ## Wilkinson matrices are symmetric and tridiagonal with pairs of nearly, but ## not exactly, equal eigenvalues. They are useful in testing the behavior and ## performance of eigenvalue solvers. ## ## @seealso{rosser, eig} ## @end deftypefn function retval = wilkinson (n) if (nargin != 1) print_usage (); endif if (! (isscalar (n) && n >= 0 && (n == fix (n)))) error ("wilkinson: N must be a non-negative integer"); endif side = ones (n-1, 1); center = abs (-(n-1)/2:(n-1)/2); retval = diag (side, -1) + diag (center) + diag (side, 1); endfunction %!assert (wilkinson (0), []) %!assert (wilkinson (1), 0) %!assert (wilkinson (2), [0.5,1;1,0.5]) %!assert (wilkinson (3), [1,1,0;1,0,1;0,1,1]) %!assert (wilkinson (4), [1.5,1,0,0;1,0.5,1,0;0,1,0.5,1;0,0,1,1.5]) ## Test input validation %!error wilkinson () %!error wilkinson (1,2) %!error <N must be a non-negative integer> wilkinson (ones (2)) %!error <N must be a non-negative integer> wilkinson (-1) %!error <N must be a non-negative integer> wilkinson (1.5)