function [D,SingularFlag,ElimFlag] = lft(D1,D2,varargin)
% LFT interconnection.

%   Copyright 1986-2010 The MathWorks, Inc.
[Dss,SingularFlag] = lft(ss(D1),ss(D2),varargin{:});
ElimFlag = (Dss.Ts~=0 && hasInternalDelay(Dss));  % internal delays need to be eliminated
try
   D = tf(Dss);
catch ME
   ctrlMsgUtils.error('Control:combination:InternalDelaysConvert2SS')
end
