proposed patch for Nicaragua, Iran, etc.
Paul Eggert
eggert at CS.UCLA.EDU
Tue Apr 12 08:21:09 UTC 2005
Thanks for mentioning that; it's higher priority to fix this, as
current timestamps are wrong in Nicaragua. Here are proposed changes
to the TZ database that take this into account, along with other
less-important changes that have been saved up.
* Nicaragua is observing DST, as of this weekend. Thanks to
Steffen Thorsen for this.
* A fix for transitions in 2025 in Iran. Thanks to Oscar van Vlijmen
for this info, and to Roozbeh Pournader and Ed Reingold for
clarifications about the Iranian calendar.
* A comment typo fixed for Mexico, and a table typo (that did not
affect any transitions) for Libya. Thanks to Jesper Norgaard Welen
for these fixes.
===================================================================
RCS file: RCS/northamerica,v
retrieving revision 2005.5
retrieving revision 2005.5.0.1
diff -pu -r2005.5 -r2005.5.0.1
--- northamerica 2005/02/07 21:19:42 2005.5
+++ northamerica 2005/04/12 08:11:31 2005.5.0.1
@@ -1427,7 +1427,7 @@ Zone America/Dawson -9:17:40 - LMT 1900
# Shanks reports that Baja was at -8:00 in 1922/1923.
# Shanks says the 1930 transition in Baja was 1930-11-16.
# Shanks reports no DST during summer 1931.
-# Shanks reports a transition at 1032-03-30 23:00, not 1932-04-01.
+# Shanks reports a transition at 1932-03-30 23:00, not 1932-04-01.
# Shanks does not report transitions for Baja in 1945 or 1948.
# Shanks reports southern Mexico transitions on 1981-12-01, not 12-23.
# Shanks says Quintana Roo switched to -6:00 on 1982-12-02, and to -5:00
@@ -1931,11 +1931,28 @@ Zone America/Montserrat -4:08:52 - LMT 1
# Nicaragua seems to be back at -6:00 but I have not been able to find when
# they changed from -5:00.
#
+# From Steffen Thorsen (2005-04-12):
+# I've got reports from 8 different people that Nicaragua just started
+# DST on Sunday 2005-04-10, in order to save energy because of
+# expensive petroleum. The exact end date for DST is not yet
+# announced, only "September" but some sites also say "mid-September".
+# Some background information is available on the President's official site:
+# http://www.presidencia.gob.ni/Presidencia/Files_index/Secretaria/Notas%20de%20Prensa/Presidente/2005/ABRIL/Gobierno-de-nicaragua-adelanta-hora-oficial-06abril.htm
+# The Decree, no 23-2005 is available here:
+# http://www.presidencia.gob.ni/buscador_gaceta/BD/DECRETOS/2005/Decreto%2023-2005%20Se%20adelanta%20en%20una%20hora%20en%20todo%20el%20territorio%20nacional%20apartir%20de%20las%2024horas%20del%2009%20de%20Abril.pdf
+#
+# From Paul Eggert (2005-04-12):
+# The decree doesn't say anything about daylight saving, but for now let's
+# assume that it is daylight saving and that they'll switch back on the
+# 2nd Sunday in September.
+#
# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
Rule Nic 1979 1980 - Mar Sun>=16 0:00 1:00 D
Rule Nic 1979 1980 - Jun Mon>=23 0:00 0 S
Rule Nic 1992 only - Jan 1 4:00 1:00 D
Rule Nic 1992 only - Sep 24 0:00 0 S
+Rule Nic 2005 only - Apr 10 0:00 1:00 D
+Rule Nic 2005 only - Sep 11 0:00 0 S
# Zone NAME GMTOFF RULES FORMAT [UNTIL]
Zone America/Managua -5:45:08 - LMT 1890
-5:45:12 - MMT 1934 Jun 23 # Managua Mean Time?
@@ -1943,7 +1960,7 @@ Zone America/Managua -5:45:08 - LMT 1890
-5:00 - EST 1975 Feb 16
-6:00 Nic C%sT 1993 Jan 1 4:00
-5:00 - EST 1998 Dec
- -6:00 - CST
+ -6:00 Nic C%sT
# Panama
# Zone NAME GMTOFF RULES FORMAT [UNTIL]
===================================================================
RCS file: RCS/africa,v
retrieving revision 2001.4
retrieving revision 2001.4.0.1
diff -pu -r2001.4 -r2001.4.0.1
--- africa 2001/10/09 17:31:30 2001.4
+++ africa 2005/04/12 08:11:31 2001.4.0.1
@@ -317,7 +317,7 @@ Rule Libya 1985 only - Apr 6 0:00 1:00
Rule Libya 1986 only - Apr 4 0:00 1:00 S
Rule Libya 1986 only - Oct 3 0:00 0 -
Rule Libya 1987 1989 - Apr 1 0:00 1:00 S
-Rule Libya 1987 1990 - Oct 1 0:00 0 -
+Rule Libya 1987 1989 - Oct 1 0:00 0 -
# Zone NAME GMTOFF RULES FORMAT [UNTIL]
Zone Africa/Tripoli 0:52:44 - LMT 1920
1:00 Libya CE%sT 1959
===================================================================
RCS file: RCS/asia,v
retrieving revision 2005.8
retrieving revision 2005.8.0.1
diff -pu -r2005.8 -r2005.8.0.1
--- asia 2005/04/04 15:24:32 2005.8
+++ asia 2005/04/12 08:11:31 2005.8.0.1
@@ -476,12 +476,33 @@ Zone Asia/Jayapura 9:22:48 - LMT 1932 No
# Thursday night of Shahrivar, but I can't give exact dates....
# I have also changed the abbreviations to what is considered correct
# here in Iran, IRST for regular time and IRDT for daylight saving time.
-
-# From Paul Eggert (2003-03-15)
+#
+# From Roozbeh Pournader (2005-04-05):
+# The text of the Iranian law, in effect since 1925, clearly mentions
+# that the true solar year is the measure, and there is no arithmetic
+# leap year calculation involved. There has never been any serious
+# plan to change that law....
+#
+# From Paul Eggert (2005-04-05):
# Go with Shanks before September 1991, and with Pournader thereafter.
-# I used Ed Reingold's cal-persia in GNU Emacs 21.2 to check Persian dates.
-# The Persian calendar is based on the sun, and dates after around 2050
-# are approximate; stop after 2037 when 32-bit time_t's overflow.
+# I used Ed Reingold's cal-persia in GNU Emacs 21.2 to check Persian dates,
+# stopping after 2037 when 32-bit time_t's overflow.
+# That cal-persia used Birashk's approximation, which disagrees with the solar
+# calendar predictions for the year 2025, so I corrected those dates by hand.
+#
+# From Oscar van Vlijmen (2005-03-30), writing about future
+# discrepancies between cal-persia and the Iranian calendar:
+# For 2091 solar-longitude-after yields 2091-03-20 08:40:07.7 UT for
+# the vernal equinox and that gets so close to 12:00 some local
+# Iranian time that the definition of the correct location needs to be
+# known exactly, amongst other factors. 2157 is even closer:
+# 2157-03-20 08:37:15.5 UT. But the Gregorian year 2025 should give
+# no interpretation problem whatsoever. By the way, another instant
+# in the near future where there will be a discrepancy between
+# arithmetical and astronomical Iranian calendars will be in 2058:
+# vernal equinox on 2058-03-20 09:03:05.9 UT. The Java version of
+# Reingold's/Dershowitz' calculator gives correctly the Gregorian date
+# 2058-03-21 for 1 Farvardin 1437 (astronomical).
#
# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
Rule Iran 1978 1980 - Mar 21 0:00 1:00 D
@@ -519,10 +540,10 @@ Rule Iran 2020 only - Mar 21 0:00 1:00 D
Rule Iran 2020 only - Sep 21 0:00 0 S
Rule Iran 2021 2023 - Mar 22 0:00 1:00 D
Rule Iran 2021 2023 - Sep 22 0:00 0 S
-Rule Iran 2024 2025 - Mar 21 0:00 1:00 D
-Rule Iran 2024 2025 - Sep 21 0:00 0 S
-Rule Iran 2026 2027 - Mar 22 0:00 1:00 D
-Rule Iran 2026 2027 - Sep 22 0:00 0 S
+Rule Iran 2024 only - Mar 21 0:00 1:00 D
+Rule Iran 2024 only - Sep 21 0:00 0 S
+Rule Iran 2025 2027 - Mar 22 0:00 1:00 D
+Rule Iran 2025 2027 - Sep 22 0:00 0 S
Rule Iran 2028 2029 - Mar 21 0:00 1:00 D
Rule Iran 2028 2029 - Sep 21 0:00 0 S
Rule Iran 2030 2031 - Mar 22 0:00 1:00 D
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