      REAL*8 FUNCTION DECDY(DATE)
C
C CONVERT HIGH RESOLUTION CALENDAR DATA TO DECIMAL DAY
C
      INTEGER*2 DATE(6)
      REAL*8 DAY,HOUR,MIN,SEC,MSEC
      MSEC = DFLOAT(DATE(6))
      SEC = DFLOAT(DATE(5)) + MSEC/1000.0D0
      MIN = DFLOAT(DATE(4)) + SEC/60.0D0
      HOUR = DFLOAT(DATE(3)) + MIN/60.0D0
      DAY = DFLOAT(DATE(2)) + HOUR/24.0D0
      DECDY = DAY
      RETURN
      END
