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[DGM]

I don't have DATE+ or DDAYS, but how about these for a start?

Code:

EXPORT DJ(X)
BEGIN
LOCAL yy,ddd,mi,mm,dd;
yy:=iquo(10000*X+14780,3652425);
ddd:=X-(365*yy+iquo(yy,4)-iquo(yy,100)+iquo(yy,400));
IF (ddd<0) THEN
  yy:=yy-1;
  ddd:=X-(365*yy+iquo(yy,4)-iquo(yy,100)+iquo(yy,400));
END;
mi:=iquo(100*ddd+52,3060);
mm:=(mi+2) MOD 12 + 1;
yy:=(yy+iquo(mi+2,12));
dd:=ddd-iquo(mi*306+5,10)+1;
RETURN yy+(mm/100)+(dd/10000);
END;

This converts a Julian date (a serial number) to a date in the form of YYYY.MMDD (the Prime format), for example 735628 will return 2014.0403 (April 3, 2014).

And this:

Code:

EXPORT JD(X)
BEGIN
LOCAL yy,mm,dd,rr;
yy:=IP(X);
mm:=IP(100*FP(X));
dd:=100*FP(100*X));
mm:=(mm+9) MOD 12;
yy:=yy-iquo(mm,10);
rr:=365*yy+iquo(yy,4)-iquo(yy,100)+iquo(yy,400)+iquo(mm*306+5,10)+(dd-1);
RETURN rr;
END;

This gives you the Julian date from an input date in the form of YYYY.MMDD.

David Motto