M-by-M unitary matrix and R is a square upper
                                      _   _
  triangular matrix. Then, the matrix B = RQ is factored as
     _
     B = PR.

  If TRANS = 'N' and 6*M &lt;= 7*N, the matrix BQ is factored as

     BQ = P ( R ),   M &gt;= N,   BQ = P ( R  Z ),   M &lt; N.
            ( 0 ) 

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