Descr iption
%　 addvar has four arguments in this order:
%　 the FIS name
%　 the type of the variable (input or output)
%　 the name of the variable
%　 the vector describing the limiting range for the variable
%　 Indices are applied to variables in the order in which they are added, so
%　 the first input variable added to a system will always be known as input
%　 variable number one for that system. Input and output variables are
%　 numbered independently.