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The leap year is February 29, not December 32 due to a Roman calendar quirk

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Re: The leap year is February 29, not December 32 due to a Roman calendar quirk

#21

Post by MrDrDr »

vivzkestrel wrote: post #9

they could have saved everyone a whole lot of trouble by having 13 months with 28 days each, no cross calendar day stuff, no leap year stuff, would be truly the most perfect calendar ever made forever and would simplify working of everything on the planet by a mile

Not sure how the fixes the leap year? The Egyptian calendar was also easier, but still drifted: https://en.m.wikipedia.org/wiki/Egyptian_calendar perhaps they could put all the extra days at the end if the year as a holiday. Some years 5 days other years 6 days.

Re: The leap year is February 29, not December 32 due to a Roman calendar quirk

#22

Post by thfuran »

roland35 wrote: post #13
foolswisdom wrote: post #11

Earlier quoted context omitted.

What? 13*28=364 So, missing ~1.25 days every year (instead of ~0.25 days each year with a 365 day calendar). How does this solve leap years?

1 or 2 "year day" holidays at the end of the calendar which aren't part of any month

I propose that we just extend "year day" to cover the entire year and leave only a single month called Null. This solves not only leap days but also leap seconds and even timezones: The time in year day isn't part of any month, day, hour, or minute so there's no problem.

Re: The leap year is February 29, not December 32 due to a Roman calendar quirk

#23

Post by Scarblac »

saalweachter wrote: post #10
Amezarak wrote: post #5

Earlier quoted context omitted.

Well, there's more to it than that: the leap day is really February 24th; there are "two" February 24ths. > Except that isn’t exactly true. The Romans did not add an extra day on February 29, but on February 24, which is where the more complicated answer begins. The Romans kept a calendar by counting backwards from specific set times of the month, the kalends (March 1), the nones (March 7) and the ides (March 15). Ju…

I would really like to go back to the earlier system, where there was no January or February, and we just stop having time in the winter until someone important announces it is the new Year in March.

Just when you think timezone databases can handle absolutely every weird thing somebody proposed somewhere...

Re: The leap year is February 29, not December 32 due to a Roman calendar quirk

#24

Post by ernesth »

vivzkestrel wrote: post #9

they could have saved everyone a whole lot of trouble by having 13 months with 28 days each, no cross calendar day stuff, no leap year stuff, would be truly the most perfect calendar ever made forever and would simplify working of everything on the planet by a mile

Well you cannot really do without leap years, but what you propose looks a lot like the pataphysical calendar: https://en.wikipedia.org/wiki/%27Pataphysics#Pataphysical_ca...

13 months of 29 days. The 29th of each month being imaginary with two exceptions, 1 annual and 1 leap.

Or more seriously, https://en.wikipedia.org/wiki/International_Fixed_Calendar

Re: The leap year is February 29, not December 32 due to a Roman calendar quirk

#25

Post by Scarblac »

MrDrDr wrote: post #21
vivzkestrel wrote: post #9

they could have saved everyone a whole lot of trouble by having 13 months with 28 days each, no cross calendar day stuff, no leap year stuff, would be truly the most perfect calendar ever made forever and would simplify working of everything on the planet by a mile

Not sure how the fixes the leap year? The Egyptian calendar was also easier, but still drifted: https://en.m.wikipedia.org/wiki/Egyptian_calendar perhaps they could put all the extra days at the end if the year as a holiday. Some years 5 days other years 6 days.

Just let it drift. The climate is changing anyway, a bit of drift will hardly be noticeable in the noise.

Re: The leap year is February 29, not December 32 due to a Roman calendar quirk

#26

Post by throw0101c »

Amezarak wrote: post #5
acadapter wrote: post #2

Summary: The historical start of the year is March 1st. That's also why some months have misleading Latin names that are off-by-2.

Well, there's more to it than that: the leap day is really February 24th; there are "two" February 24ths. > Except that isn’t exactly true. The Romans did not add an extra day on February 29, but on February 24, which is where the more complicated answer begins. The Romans kept a calendar by counting backwards from specific set times of the month, the kalends (March 1), the nones (March 7) and the ides (March 15). Ju…

>> In older writings of various kinds, you will still see people call the leap day, February 29, the bissextile day.

"bissextile" and "bis sextum" mentioned in:

* https://en.wikipedia.org/wiki/Leap_year#Julian_reform

Re: The leap year is February 29, not December 32 due to a Roman calendar quirk

#27

Post by sebastialonso »

throw0101c wrote: post #6

Funny story about the year 2000 that does not involve Y2K: "Everyone" knows that leap years occur on year divisible by 4 ('first rule'). The second rule to them is that if a year is divisible by 100 (1800, 1900, …2000), then it is not a leap year. So a lot of folks did not have their systems/software have February 29 in the year 2000. But there is a third rule: if the year is divisible by 400 (like 1600… and 2000) it…

Wow the way this is presented is super confusing, to the point that your description includes a contradiction. Specifically, of a year is divisible by 400 it's also divisible by 100, so it's both a leap year and not leap year!

Instead of showing rules as a linear list, I'd suggest it's easier to visualise it as a tree, or simpler still, as a series of nested ifs.

Re: The leap year is February 29, not December 32 due to a Roman calendar quirk

#28

Post by [deleted] »

thfuran wrote: post #22
roland35 wrote: post #13

Earlier quoted context omitted.

1 or 2 "year day" holidays at the end of the calendar which aren't part of any month

I propose that we just extend "year day" to cover the entire year and leave only a single month called Null. This solves not only leap days but also leap seconds and even timezones: The time in year day isn't part of any month, day, hour, or minute so there's no problem.

[deleted]

Re: The leap year is February 29, not December 32 due to a Roman calendar quirk

#29

Post by throw0101c »

sebastialonso wrote: post #27
throw0101c wrote: post #6

Funny story about the year 2000 that does not involve Y2K: "Everyone" knows that leap years occur on year divisible by 4 ('first rule'). The second rule to them is that if a year is divisible by 100 (1800, 1900, …2000), then it is not a leap year. So a lot of folks did not have their systems/software have February 29 in the year 2000. But there is a third rule: if the year is divisible by 400 (like 1600… and 2000) it…

Wow the way this is presented is super confusing, to the point that your description includes a contradiction. Specifically, of a year is divisible by 400 it's also divisible by 100, so it's both a leap year and not leap year! Instead of showing rules as a linear list, I'd suggest it's easier to visualise it as a tree, or simpler still, as a series of nested ifs.

> Instead of showing rules as a linear list, I'd suggest it's easier to visualise it as a tree, or simpler still, as a series of nested ifs.

Feel free to post a comment with ASCII art or (pseudo-)code. :)

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