Q, 2*N)
          On exit, if COMPQ = 'C', the leading N-by-NEIG part of
          this array contains an orthogonal basis of the right
          deflating subspace corresponding to the eigenvalues of
          aA - bB with strictly negative real part. The remaining
          part of this array is used as workspace.
          If COMPQ = 'N', this array is not referenced.

  LDQ     INTEGER
          The leading dimension of the array Q.
          LDQ &gt;= 1,           if COMPQ = 'N';
          LDQ &gt;= MA