Talk:Last Friday of each month: Difference between revisions

October 4th in year 1582 was the date in the Julian calender (the day before the switchover in some countries). The next day, the Gregorian calendar was adopted (or put into effect) in various countries, but not everywhere. The new Gregorian calender says it was October 15th. If we switched to a Mayan calendar, would we be missing ''years'' (or whatever)? Of course not. Once the Gregorian calendar was adopted, it was like the calendar was in effect all along, with a continous calendar (proleptic) backward to January 1st, year 1. No missing days. That is why there are references to ''O.S.'' (''o''ld ''s''tyle) for years previous to the adoption of the new Gregorian calendar for those people who were born before the switchover. If the Gregorian calendar wasn't proleptic, there would be no need for ''O.S.'' type of dates.

:::: The Gregorian Calendar isn't a hyrid calendar --- which is contrary to (I assume) some Java document --- one should refer to the (I can't believe I'm saying this) Vatican papers about it's description, rules, and implementation). Failing that, one could just check the bureau of weights and measurements, division of measurement standards, or whatever ... for the country you're in. It is proleptic (both in it's inception and use) and there is no discontinuity. [Nothing is really simple, the more you know about something, the more detail there is that you don't want to neccessarily know or care about]. The only point of interest is when states/countries switched over from the (whatever) older calendar(s) [in most cases, a Julian calendar] to the Gregorian calendar, and that switchover caused "missing days" when the new calendar was adopted and the old calendar was dropped. The pratical side to this is when referring to specific dates, such as (USA president) George Washington's birthday (some of old fogies still remember when GW's birthday was celebrated on the ''O.S.'' birthdate ... and then later came President's Day. The pratical side of the changeover didn't really effect many people (or contracts), there was no driver's licenses to worry about, no retirements kicking in (Social Security was a long, long way off), I suppose there was a handful of people who suddenly become over the age of consent for marriage, property ownership, inheritance, impressment, and other ... stuff, the most important was the ability to buy beer, of course, of course. The adoption of a new/different calendar (with different leapyear rules, and now, leapsecond rules) isn't a simple thing, otherwise it wouldn't have been resisted for so long by many states/countries, and, not supprising, politics/religion/posturing played a big role in this. We still squabble (a very polite term) over daylight savings times, and you won't believe the (USA) laws around the use (or not) of it --- on how they effect labor (time worked vs. time passed), 24/7 type of contracts, end-of-use clauses, a whole host of incidentals. -- [[User:Gerard Schildberger|Gerard Schildberger]] 19:10, 11 August 2012 (UTC)

Most people think that the leap year rule for the Julian calander was simple: years divisible by 4 are leap years. Not so. Julian year 4 wasn't a leap year (see if the Java code supports that). Some scholars think that Julian year 8 wasn't a leap year as well, but I can't find that reference on the "google-net" anymore.