eggert at CS.UCLA.EDU
Fri Apr 29 08:01:02 UTC 2005
Jesper Norgaard Welen <jnorgard at prodigy.net.mx> writes:
> For the Palmer station in Antarctica, the rule ArgAQ has been
> declared. But the rule ArgAQ is not used until 1965, while the rule
> is defined for year 1964.
My intent here was for ArgAQ to be a clone of the useful subset of
Arg. It's a bit easier for me to test whether they're in sync if the
lines are identical other than the labels Arg, ArgAQ, like this:
Rule Arg 1964 1966 - Mar 1 0:00 0 -
Rule ArgAQ 1964 1966 - Mar 1 0:00 0 -
EUAsia and E-EurAsia are similar.
> In the Argentina timezones, it seems that apart from the initial LMT
> (which is of course different), the Catamarca timezone and the Chubut
> timezone are in fact identical, so I suggest:
Wow, that was a mistake. Thanks for catching this. Catamarca is
bigger, so I'll remove America/Argentina/ComodRivadavia (actually,
move it to the "backward file").
> As far as I can see, the 1949-part of the PRC rule doesn't actually have
> any effect, so it could be deleted:
Thanks. I vaguely recall that was present to work around an old zic
bug. There's little point keeping it around any more.
> Unles my interpretation is wrong, both before and after the rule
> takes effect in April 2, 1945, the time in Denmark would be GMT+2
> (e.g. GMT+1 +1)
No, because Rule C-Eur said Denmark stopped observing DST on 1944-10-02.
> As a side-question, I haven't been able to check this with any Time
> Zone Converter (the web version has a cutoff date of 1970). Is there
> any way to check this by a program, and which?
I use zdump (from tzcode) compiled on Solaris. GNU/Linux would work
too I think.
> The page http://www.hum.aau.dk/~poe/tid/tine/DanskTid.htm says that
> the law was in effect from 1. January 1894, not from April.
> The page http://www.retsinfo.dk/_GETDOCI_/ACCN/A18930008330-REGL
> confirms this
Thanks for catching that. Shanks agrees with that. I had gone with
Whitman, but it's quite clear Whitman and I were mistaken.
Does either reference say what time-of-day that Standard Time was
introduced? In the US, for example, the transition occurred at 12:00
new time (not old time). This leads to interesting lines like this:
# Zone NAME GMTOFF RULES FORMAT [UNTIL]
Zone America/New_York -4:56:02 - LMT 1883 Nov 18 12:03:58
> in another related law, the effecting DST changes are stated
> explicitly: to be from 6.th. of April 1980 at 2.00 to 28.th. of
> September 1980 at 2.00. If this is true, this differs slightly from
> the EU rule in that DST runs to 2.00, not 3.00.
It would have been odd for the 1980 transitions to disagree with both
old Danish tradition (1945-1948) and with the then-current EU rules.
For now, how about if we assume that the 02:00 of the above source
refers to standard time, not wall-clock time, and so the EU rules were
> This in effect confirms the information from Shanks, although there
> is a discrepancy for 1940-1942.
Hmm, sorry, I don't see the discrepancy. That source says DST was in
effect from 1940-08-11 to 1942-11-02. Shanks gives 1940-08-10 23:00
to 1942-11-02 03:00. These pretty much agree. Norway's rules were
under German control at the time, so it's reasonable to use C-Eur
rules (same as Germany) for that period.
Thanks again for your detailed comments. I'll submit patches along
the lines described above in my next patch proposal.
More information about the tz