The Math of Leap Days

The Bad Astronomer writes "We have leap days every four years because the Earth's day and year don't divide evenly. But there's more to it than that... a lot more. A year isn't exactly 365.25 days long, and that leads to needing more complicated math and rules for when we do and don't have a leap year. If you've ever wanted to see that math laid out, now's your chance, and it only comes along every four years. Except every hundred years. Except every four hundred years."

Comments

Complicated?

[Anonymous Coward]

I think we have different definitions of complicated.

Re:Our whole calendar is messed up.

[dmt0]

The whole 7 day week is rather random too- based on some out-of-date dogma that is probably mistranslated. (the original word in Genesis translated as "day" was more accurately "a period of time" although it was often "day" but not necessarily) - so we force the meaning of "day" onto it and have a 7 day week. Silly number.

Let's make a week 10 days- a much more logical number.

Actually 7-day week makes sense if you have a 28-day month.

Re:Duh.

[egamma]

No, the REAL nightmare for programmers is daylight savings time. Especially in the spring, when local times jump back and repeat. Ugh.

That's why you should save the time in UTC format, and then let the OS help you translate that into a display time.