)**H * op(B).

  The Schur factorization of a square matrix A is given by
            H
     A = QSQ ,

  where Q is unitary and S is an N-by-N upper triangular matrix.
  If A has already been factored prior to calling the routine, then
  the factors Q and S may be supplied and the initial factorization
  omitted.

  If TRANS = 'N' and 6*M &gt; 7*N, the matrix B is factored as
  (QR factorization)
         _   _
     B = P ( R ), 
           ( 0 )
        _                                 _
  where P is an 