,subname,<span class="string">', check keywords'</span>])
0071     <span class="keyword">end</span>;
0072     
0073     <span class="keyword">switch</span>(keyword(1:3))
0074     
0075     <span class="keyword">case</span> <span class="string">'gri'</span>
0076         grid_fname = varargin{i+1};
0077         have_grid = true;
0078     <span class="keyword">case</span> <span class="string">'coo'</span>
0079         coord = varargin{i+1};
0080         <span class="keyword">if</span>(coord(1:3)==<span class="