Mercurial > octave-nkf
view scripts/polynomial/polyaffine.m @ 14327:4d917a6a858b stable
doc: Use Octave coding conventions in @example blocks of docstrings.
* accumarray.m, accumdim.m, bar.m, base2dec.m, bincoeff.m, bitcmp.m, bitset.m,
celldisp.m, chop.m, clabel.m, cloglog.m, colon.m, compass.m, computer.m,
contour3.m, contourc.m, corr.m, cstrcat.m, ctime.m, cylinder.m, date.m,
dec2base.m, demo.m, dir.m, dlmwrite.m, expm.m, ezcontourf.m, ezcontour.m,
ezmeshc.m, ezmesh.m, ezplot.m, ezsurfc.m, ezsurf.m, feather.m, findobj.m,
flipdim.m, fplot.m, genvarname.m, getfield.m, hankel.m, hilb.m, hist.m,
idivide.m, index.m, int2str.m, interp1.m, is_leap_year.m, ismember.m,
isocolors.m, isonormals.m, isosurface.m, kurtosis.m, legendre.m, linkprop.m,
logit.m, logm.m, __makeinfo__.m, __marching_cube__.m, median.m, mkoctfile.m,
moment.m, mpoles.m, orderfields.m, pcg.m, pcr.m, plot3.m, plotmatrix.m,
polyaffine.m, polygcd.m, poly.m, polyout.m, print.m, qp.m, quadgk.m, qzhess.m,
randi.m, rat.m, refreshdata.m, residue.m, rose.m, rot90.m, saveas.m, saveobj.m,
shiftdim.m, skewness.m, spaugment.m, spdiags.m, sqp.m, stem.m, str2num.m,
strcat.m, strjust.m, strread.m, strsplit.m, structfun.m, subplot.m,
subsindex.m, substruct.m, surfl.m, surfnorm.m, svds.m, uimenu.m, union.m,
voronoi.m, warning_ids.m, wblpdf.m: Use Octave coding conventions in
@example blocks of docstrings.
author | Rik <octave@nomad.inbox5.com> |
---|---|
date | Sat, 04 Feb 2012 22:12:50 -0800 |
parents | 72c96de7a403 |
children | ce2b59a6d0e5 |
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## Copyright (C) 2009-2012 Tony Richardson, Jaroslav Hajek ## ## 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} {} polyaffine (@var{f}, @var{mu}) ## Return the coefficients of the polynomial vector @var{f} after an affine ## transformation. If @var{f} is the vector representing the polynomial f(x), ## then @code{@var{g} = polyaffine (@var{f}, @var{mu})} is the vector ## representing: ## ## @example ## g(x) = f( (x - @var{mu}(1)) / @var{mu}(2) ) ## @end example ## ## @seealso{polyval, polyfit} ## @end deftypefn function g = polyaffine (f, mu) if (nargin != 2) print_usage (); endif if (! isvector (f)) error ("polyaffine: F must be a vector"); endif if (! isvector (mu) || length (mu) != 2) error ("polyaffine: MU must be a two-element vector"); endif lf = length (f); ## Ensure that f is a row vector if (rows (f) > 1) f = f.'; endif g = f; ## Scale. if (mu(2) != 1) g = g ./ (mu(2) .^ (lf-1:-1:0)); endif ## Translate. if (mu(1) != 0) w = (-mu(1)) .^ (0:lf-1); ii = lf:-1:1; g = g(ii) * (toeplitz (w) .* pascal (lf, -1)); g = g(ii); endif endfunction %!demo %! f = [1/5 4/5 -7/5 -2]; %! g = polyaffine (f, [1, 1.2]); %! x = linspace (-4, 4, 100); %! plot(x, polyval (f, x), x, polyval (g, x)); %! legend ("original", "affine"); %! axis ([-4 4 -3 5]); %! grid ("on"); %!test %! f = [1/5 4/5 -7/5 -2]; %! mu = [1, 1.2]; %! g = polyaffine (f, mu); %! x = linspace (-4, 4, 100); %! assert (polyval (f, x, [], mu), polyval (g, x), 1e-10);