maint: Use Octave coding convention for cuddled parenthis in function calls with empty argument lists. Example: func() => func () * dynamic.txi, func.txi, oop.txi, var.txi, embedded.cc, fortdemo.cc, funcdemo.cc, paramdemo.cc, stringdemo.cc, unwinddemo.cc, Array.cc, Array.h, CColVector.cc, CDiagMatrix.h, CMatrix.cc, CNDArray.cc, CRowVector.cc, CSparse.cc, CmplxGEPBAL.cc, EIG.cc, MSparse.cc, MatrixType.cc, Sparse-op-defs.h, Sparse-perm-op-defs.h, Sparse.cc, Sparse.h, SparseCmplxCHOL.cc, SparseCmplxCHOL.h, SparseCmplxLU.cc, SparseCmplxQR.cc, SparseCmplxQR.h, SparseQR.cc, SparseQR.h, SparsedbleCHOL.cc, SparsedbleCHOL.h, SparsedbleLU.cc, SparsedbleLU.h, base-lu.cc, cmd-hist.cc, dColVector.cc, dDiagMatrix.h, dMatrix.cc, dNDArray.cc, dRowVector.cc, dSparse.cc, dbleCHOL.cc, dbleGEPBAL.cc, dim-vector.cc, eigs-base.cc, f2c-main.c, fCColVector.cc, fCDiagMatrix.h, fCMatrix.cc, fCNDArray.cc, fCRowVector.cc, fCmplxGEPBAL.cc, fColVector.cc, fDiagMatrix.h, fEIG.cc, fMatrix.cc, fNDArray.cc, fRowVector.cc, file-ops.cc, file-stat.cc, floatCHOL.cc, floatGEPBAL.cc, idx-vector.h, lo-specfun.cc, lo-sysdep.cc, mx-inlines.cc, oct-binmap.h, oct-convn.cc, oct-md5.cc, oct-mem.h, oct-rand.cc, oct-syscalls.cc, randgamma.c, randmtzig.c, sparse-base-chol.cc, sparse-base-chol.h, sparse-base-lu.cc, sparse-dmsolve.cc, tempname.c, curl.m, divergence.m, randi.m, dlmwrite.m, edit.m, getappdata.m, what.m, getarchdir.m, install.m, installed_packages.m, repackage.m, unload_packages.m, colorbar.m, figure.m, isosurface.m, legend.m, loglog.m, plot.m, plot3.m, plotyy.m, polar.m, __errplot__.m, __ghostscript__.m, __marching_cube__.m, __plt__.m, __scatter__.m, semilogx.m, semilogy.m, trimesh.m, trisurf.m, demo.m, test.m, datetick.m, __delaunayn__.cc, __dsearchn__.cc, __fltk_uigetfile__.cc, __glpk__.cc, __init_fltk__.cc, __lin_interpn__.cc, __magick_read__.cc, __pchip_deriv__.cc, balance.cc, bsxfun.cc, ccolamd.cc, cellfun.cc, chol.cc, daspk.cc, dasrt.cc, dassl.cc, dmperm.cc, eig.cc, eigs.cc, fftw.cc, filter.cc, find.cc, kron.cc, lookup.cc, lsode.cc, matrix_type.cc, md5sum.cc, mgorth.cc, qr.cc, quad.cc, rand.cc, regexp.cc, symbfact.cc, tril.cc, urlwrite.cc, op-bm-bm.cc, op-cdm-cdm.cc, op-cell.cc, op-chm.cc, op-cm-cm.cc, op-cm-scm.cc, op-cm-sm.cc, op-cs-scm.cc, op-cs-sm.cc, op-dm-dm.cc, op-dm-scm.cc, op-dm-sm.cc, op-fcdm-fcdm.cc, op-fcm-fcm.cc, op-fdm-fdm.cc, op-fm-fm.cc, op-int.h, op-m-m.cc, op-m-scm.cc, op-m-sm.cc, op-pm-pm.cc, op-pm-scm.cc, op-pm-sm.cc, op-range.cc, op-s-scm.cc, op-s-sm.cc, op-sbm-sbm.cc, op-scm-cm.cc, op-scm-cs.cc, op-scm-m.cc, op-scm-s.cc, op-scm-scm.cc, op-scm-sm.cc, op-sm-cm.cc, op-sm-cs.cc, op-sm-m.cc, op-sm-s.cc, op-sm-scm.cc, op-sm-sm.cc, op-str-str.cc, op-struct.cc, bitfcns.cc, data.cc, debug.cc, dynamic-ld.cc, error.cc, gl-render.cc, graphics.cc, graphics.in.h, load-path.cc, ls-hdf5.cc, ls-mat5.cc, ls-mat5.h, ls-oct-ascii.cc, ls-oct-ascii.h, mex.cc, mk-errno-list, oct-map.cc, oct-obj.h, oct-parse.yy, octave-config.in.cc, ov-base-int.cc, ov-base-mat.cc, ov-base.cc, ov-bool-mat.cc, ov-bool-sparse.cc, ov-bool.cc, ov-cell.cc, ov-class.cc, ov-class.h, ov-cx-mat.cc, ov-cx-sparse.cc, ov-fcn-handle.cc, ov-flt-cx-mat.cc, ov-flt-re-mat.cc, ov-intx.h, ov-range.h, ov-re-mat.cc, ov-re-sparse.cc, ov-str-mat.cc, ov-struct.cc, ov-usr-fcn.h, ov.h, pr-output.cc, pt-id.cc, pt-id.h, pt-mat.cc, pt-select.cc, sparse.cc, symtab.cc, symtab.h, syscalls.cc, toplev.cc, txt-eng-ft.cc, variables.cc, zfstream.cc, zfstream.h, Dork.m, getStash.m, myStash.m, Gork.m, Pork.m, myStash.m, getStash.m, myStash.m, getStash.m, myStash.m, fntests.m: Use Octave coding convention for cuddled parenthis in function calls with empty argument lists.

## Copyright (C) 2007-2012 Sylvain Pelissier
##
## 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} {[@var{x}, @var{y}, @var{z}] =} ellipsoid (@var{xc}, @var{yc}, @var{zc}, @var{xr}, @var{yr}, @var{zr}, @var{n})
## @deftypefnx {Function File} {} ellipsoid (@var{h}, @dots{})
## Generate three matrices in @code{meshgrid} format that define an
## ellipsoid.  Called with no return arguments, @code{ellipsoid} calls
## directly @code{surf (@var{x}, @var{y}, @var{z})}.  If an axes handle
## is passed as the first argument, the surface is plotted to this
## set of axes.
## @seealso{sphere}
## @end deftypefn

## Author: Sylvain Pelissier <sylvain.pelissier@gmail.com>

function [xx, yy, zz] = ellipsoid (varargin)

  [h, varargin, nargin] = __plt_get_axis_arg__ ((nargout > 0), "ellipsoid",
                                                varargin{:});

  if (nargin != 6 && nargin != 7)
    print_usage ();
  endif

  xc = varargin{1};
  yc = varargin{2};
  zc = varargin{3};
  xr = varargin{4};
  yr = varargin{5};
  zr = varargin{6};

  if (nargin == 6)
    n = 20;
  else
    n = varargin{7};
  endif

  theta = linspace (0, 2 * pi, n + 1);
  phi = linspace (-pi / 2, pi / 2, n + 1);
  [theta, phi] = meshgrid (theta, phi);

  x = xr .* cos (phi) .* cos (theta) + xc;
  y = yr .* cos (phi) .* sin (theta) + yc;
  z = zr .* sin (phi) + zc;

  if (nargout > 0)
    xx = x;
    yy = y;
    zz = z;
  else
    surf (h, x, y, z);
  endif

endfunction


%!demo
%! clf;
%! ellipsoid (0, 0, 1, 2, 3, 4, 20);