atrix in the columns 2 to N/2+1 of this array
          contains the matrix Vout (see METHOD); otherwise, it
          contains the matrix V obtained just before the application
          of the periodic QZ algorithm.

  LDFG    INTEGER
          The leading dimension of the array FG.
          LDFG &gt;= MAX(1, N/2).

  NEIG    (output) INTEGER
          If COMPQ = 'C', the number of eigenvalues in aS - bH with
          strictly negative real part.

  Q       (output) DOUBLE PRECISION array, dimension (LD