DEFINE FUNCTION

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DEFINE FUNCTION

            [SIC\]DEFINE FUNCTION NAME(X,Y,Z) Expression(X,Y,Z)

        Define  an  arithmetic  user  function of several variables. The maximum
        number of variables is 8. The function definition can reference  any  of
        the  known  mathematic  operators and intrinsic or program defined func-
        tions, but not previously defined user  functions  (i.e.  user  function
        definition is not recursive).