1 ## Copyright (C) 2007-2012 Michael Goffioul
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
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13 ## General Public License for more details.
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16 ## along with Octave; see the file COPYING. If not, see
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20 ## @deftypefn {Function File} {[@var{x}, @var{y}, @var{z}] =} sphere (@var{n})
21 ## @deftypefnx {Function File} {} sphere (@var{h}, @dots{})
22 ## Generate three matrices in @code{meshgrid} format, such that
23 ## @code{surf (@var{x}, @var{y}, @var{z})} generates a unit sphere.
24 ## The matrices of @code{@var{n}+1}-by-@code{@var{n}+1}. If @var{n} is
25 ## omitted then a default value of 20 is assumed.
27 ## Called with no return arguments, @code{sphere} call directly
28 ## @code{surf (@var{x}, @var{y}, @var{z})}. If an axes handle is passed
29 ## as the first argument, the surface is plotted to this set of axes.
33 function [xx, yy, zz] = sphere (varargin)
35 [h, varargin, nargin] = __plt_get_axis_arg__ ((nargout > 0), "sphere",
45 theta = linspace (0, 2*pi, n+1);
46 phi = linspace (-pi/2, pi/2, n+1);
47 [theta,phi] = meshgrid (theta, phi);
49 x = cos (phi) .* cos (theta);
50 y = cos (phi) .* sin (theta);