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SUBROUTINE sla_DJCL (DJM, IY, IM, ID, FD, J)
*+
* - - - - -
* D J C L
* - - - - -
*
* Modified Julian Date to Gregorian year, month, day,
* and fraction of a day.
*
* Given:
* DJM dp modified Julian Date (JD-2400000.5)
*
* Returned:
* IY int year
* IM int month
* ID int day
* FD dp fraction of day
* J int status:
* 0 = OK
* -1 = unacceptable date (before 4701BC March 1)
*
* The algorithm is derived from that of Hatcher 1984
* (QJRAS 25, 53-55).
*
* P.T.Wallace Starlink 27 April 1998
*
* Copyright (C) 1998 Rutherford Appleton Laboratory
*-
IMPLICIT NONE
DOUBLE PRECISION DJM
INTEGER IY,IM,ID
DOUBLE PRECISION FD
INTEGER J
DOUBLE PRECISION F,D
INTEGER JD,N4,ND10
* Check if date is acceptable
IF (DJM.LE.-2395520D0.OR.DJM.GE.1D9) THEN
J=-1
ELSE
J=0
* Separate day and fraction
F=MOD(DJM,1D0)
IF (F.LT.0D0) F=F+1D0
D=ANINT(DJM-F)
* Express day in Gregorian calendar
JD=NINT(D)+2400001
N4=4*(JD+((6*((4*JD-17918)/146097))/4+1)/2-37)
ND10=10*(MOD(N4-237,1461)/4)+5
IY=N4/1461-4712
IM=MOD(ND10/306+2,12)+1
ID=MOD(ND10,306)/10+1
FD=F
J=0
END IF
END
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