On Thu, 18 Aug 2011 16:15:27 +0200, [UTF-8?]SaaÅ¡ha Metsärantala wrote
> > The date 2012-02-30 using the (very short lived) Swedish calendar is
still a valid date
> Well, 1712-02-30 is "valid" in this calendar, but not in the (gregorian)
> astronomical one and thus nothing for today's EDTF without conversion.
There are a very large number of calendars. Some like the Swedish are no
longer in use but others like the Hebrew/Jewish are still actively being
used and developed. Dates from one to the other must be converted. Sometimes
its easy.. and sometimes its quite difficult or possible only with lower
> AFAIK, no plans were ever made at all to consider 2012-02-30 as a valid
> date within the Swedish calendar. Have you some references about the
> "2012-02-30" issue?
Do not confuse a calendar with its common use. The Swedish calendar
became "obsolete" in 1711 when Sweden decided to return to a Julian based
calendar starting in 1712. A day was added to the leap year allowing for a
30 Feb 1712. While the calendar used was more or less Julian based it did
have a number of "Swedish tweeks". After 40 years of evolutionary tweeking
(a tradition of self-declared "Revolutions in little steps")of the Julan
calendar Sweden adopted yet another calendar: the Gregorian (well not
really.. more a Swedish variant but..).
[as a side note on use: its quite common for computer programs to internally
use a Julian calendar to store dates given the simplicity of arithmetic over
the International (Gregorian).]
The whole point is.. These are all unique calendars and not the same as the
International calendar currently in use..
> Anyway, maybe we could just keep a record of this issue and move this
> discussion to the next phase.
Edward C. Zimmermann, NONMONOTONIC LAB