1 ## Copyright (C) 2007-2012 Sylvain Pelissier
3 ## This file is part of Octave.
5 ## Octave is free software; you can redistribute it and/or modify it
6 ## under the terms of the GNU General Public License as published by
7 ## the Free Software Foundation; either version 3 of the License, or (at
8 ## your option) any later version.
10 ## Octave is distributed in the hope that it will be useful, but
11 ## WITHOUT ANY WARRANTY; without even the implied warranty of
12 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 ## General Public License for more details.
15 ## You should have received a copy of the GNU General Public License
16 ## along with Octave; see the file COPYING. If not, see
17 ## <http://www.gnu.org/licenses/>.
20 ## @deftypefn {Function File} {[@var{x}, @var{y}, @var{z}] =} ellipsoid (@var{xc}, @var{yc}, @var{zc}, @var{xr}, @var{yr}, @var{zr}, @var{n})
21 ## @deftypefnx {Function File} {} ellipsoid (@var{h}, @dots{})
22 ## Generate three matrices in @code{meshgrid} format that define an
23 ## ellipsoid. Called with no return arguments, @code{ellipsoid} calls
24 ## directly @code{surf (@var{x}, @var{y}, @var{z})}. If an axes handle
25 ## is passed as the first argument, the surface is plotted to this
30 ## Author: Sylvain Pelissier <sylvain.pelissier@gmail.com>
32 function [xx, yy, zz] = ellipsoid (varargin)
34 [h, varargin, nargin] = __plt_get_axis_arg__ ((nargout > 0), "ellipsoid",
37 if (nargin != 6 && nargin != 7)
54 theta = linspace (0, 2 * pi, n + 1);
55 phi = linspace (-pi / 2, pi / 2, n + 1);
56 [theta, phi] = meshgrid (theta, phi);
58 x = xr .* cos (phi) .* cos (theta) + xc;
59 y = yr .* cos (phi) .* sin (theta) + yc;
60 z = zr .* sin (phi) + zc;
74 %! ellipsoid (0, 0, 1, 2, 3, 4, 20);