ey transform of the input signal.
          On exit with SCR = 'O', this array contains the
          bit-reversed Hartley transform.

  W       (input/output) DOUBLE PRECISION array,
                         dimension (N - LOG2(N))
          On entry with WGHT = 'A', this array must contain the long
          weight vector computed by a previous call of this routine
          with the same value of N. If WGHT = 'N', the contents of
          this array on entry is ignored.
          On exit, this array con