Brazil zoneinfo corrections.
eggert at twinsun.com
Sat Oct 18 07:31:44 UTC 2003
Thanks for your proofreading of the history of time zones and daylight
saving time of Brazil. Here are some thoughts about your comments.
> From: Rodrigo Severo [mailto:rodrigo.lists at fabricadeideias.com]
> Sent: Thursday, October 16, 2003 7:31 PM
> 1. The effects of decrees 52700 (1963-10-18) and 53071 (1963-12-03)
> weren't correctly represented by the data as what they really have done
> was to make a set of states start DST at 1963-10-23 00:00 and the rest
> of the country to start DST at 1963-12-09 00:00.
As far as I can see, the current tz data does that. The tz source
looks different from what you're proposing, but the actual transitions
already equal what would be generated by the proposed change. For
example, for America/Manuas the 1963 transition is currently this:
Mon Dec 9 03:59:59 1963 UTC = Sun Dec 8 23:59:59 1963 AMT isdst=0
Mon Dec 9 04:00:00 1963 UTC = Mon Dec 9 01:00:00 1963 AMST isdst=1
and this transition isn't affected by the proposed change. So I don't
see the need for this part of the change.
> 2. The starting time of DST for 1966 was wrong as the 57843 decree
> stablishes that DST shall [end] at 1966-03-01 01:00 and on 1st of March
> 00:00 from 1967 and on.
I'm inclined to think that this may be a typographical error or
ambiguity in decree 57,843 <http://pcdsh01.on.br/HV57843.htm>. It'd
be unusual for Brazil to change at any time other than midnight. This
reminds me of the 24-hour error in Decree 4,844 this year (though the
latter error was corrected after a couple of days). However, I don't
read Portuguese so I'm not really qualified to interpret any wording
problems in decree 57,843.
> 3. Decree 1252 (1994-09-22) defines that the previous states minus AM
> _AND_ MT states would have DST during 1994/1995 summer. The author of
> the previous comment probably relied on the Brazilian National
> Observatory resume of the decree - which is wrong - and not on the
> actual decree itself (also available at the Brazilian National
> Observatory site).
Thanks for noticing that bug.
> Fix: Include all DSTs for Pernambuco after 1988
Thanks for that correction too.
> create new zone Atol_das_Rocas for the atlantic islands.
I don't think this zone is needed, as there is no permanent settlement
on any of those islands. There is a military oceanographic station on
Trindade but my impression is that it is not occupied all the time.
If my impression is incorrect we need to find out what time is
actually observed by the three dozen Brazilian marines who are ordered
to live there.
> 5. America/Sao_Paulo zone had a DST during the whole 1964. I can't see
> where it came from. There is no decree mentioning it.
It's not all of 1964, it's only the period from 1963-10-23 00:00 to
1964-03-01 00:00. I think issue (5) is the same as issue (1) above.
It's merely a different way to split the work between the Zone and the
Rule lines; the actual transitions are the same regardless of whether
the proposed patch is applied.
Here's a diff to reflect the above comments. I'll include something
like this in my next proposed patch. Again, thanks for your careful
proofreading of the data.
--- southamerica 2003/10/06 13:34:33 2003.4
+++ southamerica 2003/10/18 07:10:23
@@ -351,6 +351,9 @@ Rule Brazil 1965 only - Mar 31 0:00 0 -
# Decree <a href="http://pcdsh01.on.br/HV57303.htm">57,303</a> (1965-11-22)
Rule Brazil 1965 only - Dec 1 0:00 1:00 S
# Decree <a href="http://pcdsh01.on.br/HV57843.htm">57,843</a> (1966-02-18)
+# From Paul Eggert (2003-10-17):
+# Rodrigo Severo writes that Decree 57,843 says DST ends 1966-03-01 at
+# 01:00, not at 00:00. For now, assume this is a typo.
Rule Brazil 1966 1968 - Mar 1 0:00 0 -
Rule Brazil 1966 1967 - Nov 1 0:00 1:00 S
# Decree <a href="http://pcdsh01.on.br/HV63429.htm">63,429</a> (1968-10-15)
@@ -390,9 +393,9 @@ Rule Brazil 1993 only - Jan 31 0:00 0 -
# Decree <a href="http://pcdsh01.on.br/HV942.htm">942</a> (1993-09-28)
# adopted by same states, plus AM.
# Decree <a href="http://pcdsh01.on.br/HV1252.htm">1,252</a> (1994-09-22)
-# adopted by same states, minus AM.
+# adopted by same states, minus AM and MT.
# Decree <a href="http://pcdsh01.on.br/HV1636.htm">1,636</a> (1995-09-14)
-# adopted by same states, plus TO.
+# adopted by same states, plus MT and TO.
# Decree <a href="http://pcdsh01.on.br/HV1674.htm">1,674</a> (1995-10-13)
# adds AL, SE.
Rule Brazil 1993 1995 - Oct Sun>=11 0:00 1:00 S
@@ -455,11 +458,17 @@ Rule Brazil 2003 max - Oct Sun>=15 0:00
# Zone NAME GMTOFF RULES FORMAT [UNTIL]
-# Atlantic islands: Fernando de Noronha, Trindade, Martin Vaz,
-# Atol das Rocas, and Penedos de Sao Pedro e Sao Paulo
+# Fernando de Noronha
Zone America/Noronha -2:09:40 - LMT 1914
-2:00 Brazil FN%sT 1990 Sep 17
+ -2:00 - FNT 1999 Sep 30
+ -2:00 Brazil FN%sT 2000 Oct 15
+ -2:00 - FNT 2001 Sep 13
+ -2:00 Brazil FN%sT 2002 Oct 1
-2:00 - FNT
+# Other Atlantic islands have no permanent settlement.
+# These include Trindade, Martin Vaz,
+# Atol das Rocas, and Penedos de Sao Pedro e Sao Paulo.
# Amapa (AP), east Para (PA)
# East Para includes Belem, Maraba, Serra Norte, and Sao Felix do Xingu.
@@ -528,6 +537,8 @@ Zone America/Campo_Grande -3:38:28 - LMT
# Mato Grosso (MT)
Zone America/Cuiaba -3:44:20 - LMT 1914
+ -4:00 Brazil AM%sT 1994 Sep 22
+ -4:00 - AMT 1995 Sep 14
-4:00 Brazil AM%sT 2003 Sep 24
-4:00 - AMT
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