function Vo=getlevels(Z,V);
% GETLEVELS Computes vector of levels for contouring purposes
%           V=getlevels(Z,V) takes the input Z matrix and V argument,
%           and computes the same V vector generated by the built-in
%           contouring routines. This is necessary for compatability
%           reasons.

% Author: R. Pawlowicz (IOS) rich@ios.bc.ca
%         16/mar/95

if (length(V) <= 1)  % Get default contour levels if needed
  minz = min(min(Z(finite(Z))));
  maxz = max(max(Z(finite(Z))));
  if isempty(V) CS=contourc([minz maxz ; minz maxz]);
  else          CS=contourc([minz maxz ; minz maxz],V);
  end
  ii = 1;    % Find the levels
  Vo = [];
  while (ii < size(CS,2)),
    Vo=[Vo CS(1,ii)];
    ii = ii + CS(2,ii) + 1;
  end
else
 Vo=sort(V); % return in ascending order otherwise filling may not work properly
end