 array
          contains the matrix YQ.

  LDYQ    INTEGER
          The leading dimension of the array YQ.  LDYQ &gt;= MAX(1,N).

  CSL     (output) DOUBLE PRECISION array, dimension (2*NB)
          On exit, the first 2NB elements of this array contain the
          cosines and sines of the symplectic Givens rotations
          applied from the left-hand side used to compute the
          reduction.

  CSR     (output) DOUBLE PRECISION array, dimension (2*NB)
          On exit, the first 2NB-2 elements o