Re: Julian Dates package?

[kst@aonix.com (Keith Thompson)]

Mike Stark <michael.e.stark@GSFC.NASA.GOV> wrote:
> I suggest using package Calendar, since it provides subtraction operator
> for two absolute times, yielding elapsed times.  To compute number of
> days, create a birthdate and current date of type calendar.time, with
> the seconds of day set to zero.  This will give you a (fixed point)
> number of seconds.  Divide that number by 86,400 and you now have
> the number of days.

That's not guaranteed to work.  The subtraction operation returns a
result of type Duration, which is a fixed-point type with a minimum range
of -86400.0 .. +86400.0 (i.e., +/- 1 day).  Thus, you can't portably
subtract two Calendar.Time values more than a day apart.

-- 
Keith Thompson (The_Other_Keith) kst@aonix.com <http://www.aonix.com> <*>
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