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Re: Calendar

Regarding the formula that Brian Whatcott presented for date-to-day of week
conversions Leigh wrote:

The formula given doesn't work anywhere before October 1582,
and it doesn't work a lot of places later than that, up to
before 1917 in Russia.

I might add that it *still* doesn't work for dates on the religious calendar
of the Russian Orthodox Church (and maybe a couple of other Eastern Orthodox
Churches as well). This point that Leigh brought up about the fact that we
do not use the Julian calendar any longer, but rather use the Gregorian
calendar points up the misleading nature of the name given to the date
integer which the formula calculates (before the mod 7 operation). Brian
said this integer is called the "Julian Day Number". I think that a less
misleading name for this integer would be the "Gregorian Day Number".

David Bowman
dbowman@gtc.georgetown.ky.us