       = 'U':  The given matrix U is updated by the unitary
                  transformations used in the reduction.

  UPLO    CHARACTER*1
          Indicates whether the user wishes the pair (A,C) to be
          reduced to upper or lower observer Hessenberg form as
          follows:
          = 'U':  Upper observer Hessenberg form;
          = 'L':  Lower observer Hessenberg form.

</PRE>
<B>Input/Output Parameters</B>
<PRE>
  N       (input) INTEGER
          The actual state dimension, i.e. the order 