Re: February 30th 2000

From: Rogier Wolff (R.E.Wolff@BitWizard.nl)
Date: Thu Jan 13 2000 - 17:56:56 EST


Chris Wedgwood wrote:
> > Our current (gregorian) rules come to
> >
> > 365 + 1/4 - 1/100 + 1/400 = 365.2425
> >
> > The difference with 365.24219878 is: .00030122, which means that every
> > 3320 years or so, we're having one too many leap years. So, I would
> > suggest that we make the year 3300 a leap year. And 6600, 9900, 13300
> > and so on.... (*)
>
> Years evenly divisible by 4000 are _not_ leap years. I only know of
> one (nay, two shortly) piece of code which take this into account...

Although my calculation shows that this would not be a bad idea, the
modern world has agreed upon the Gregorian calender which simply doesn't
take this into account.

There are a few "arbitrary" things that we agree upon in this world.
Elecrons carry a negative charge, and we have a rule for "leap years"
that can be done by heart.

We could for instance say:

Year Y is a leap year if and only if:

        int (Y * 365.24219878) == 366 + int ((Y-1) * 365.24219878)

Works perfectly for about a few million years, provided the earth's
rotation doesn't change too much. You'd get streaks of about 32 years
where the leap year is on the same year mod 4, and then there would be
5 years between two leap years.

Good thinking, but no cigar. We agreed upon the gregorian calendar
which has a different rule. (makes it easier to do things without a
computer that can easily calculate this stuff to 6 decimal places).

                                Roger.

-- 
** R.E.Wolff@BitWizard.nl ** http://www.BitWizard.nl/ ** +31-15-2137555 **
*-- BitWizard writes Linux device drivers for any device you may have! --*
 "I didn't say it was your fault. I said I was going to blame it on you."

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