</A>

<P>
<B><FONT SIZE="+1">Purpose</FONT></B>
<PRE>
  To compute orthogonal transformations Q and Z such that the
  transformed pencil Q'(sE-A)Z is in upper block triangular form,
  where E is an M-by-N matrix in column echelon form (see SLICOT
  Library routine MB04UD) and A is an M-by-N matrix.

  If MODE = 'B', then the matrices A and E are transformed into the
  following generalized Schur form by unitary transformations Q1
  and Z1 :

                   | sE(eps,inf)-A(eps,inf) |      X     |
     Q1