[tz] FW: [Ext] The TZ Coordination
Paul Eggert
eggert at cs.ucla.edu
Sun May 31 22:23:27 UTC 2020
On 5/31/20 7:03 AM, Milamber wrote:
> Perhaps, you can modify the (predict) rules for next years : if the end of
> Ramadan is a (probable) Friday or Saturday (and so the 2 day off is on a
> weekend), the next time shift will be the next weekend.
Thanks for the info. I installed the attached patch to change the predictions
accordingly. Of course these predictions are somewhat fanciful if the Moroccan
government itself doesn't know when the transitions will be.
-------------- next part --------------
From e30fe68d4448a79d8ac95bf6ae81bb344328eb3c Mon Sep 17 00:00:00 2001
From: Paul Eggert <eggert at cs.ucla.edu>
Date: Sun, 31 May 2020 15:17:11 -0700
Subject: [PATCH] Predict Morocco spring-forward after Eid al-Fitr
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
(Thanks to Milamber.)
* NEWS: Mention this.
* africa (Morocco): Change ‘1+’ to ‘+ 2’ in the commented-out
code, and alter the prdicted rules accordingly for 2023-2085.
---
NEWS | 7 +++++++
africa | 45 +++++++++++++++++++++++++++++----------------
2 files changed, 36 insertions(+), 16 deletions(-)
diff --git a/NEWS b/NEWS
index ac491e1..8362dcc 100644
--- a/NEWS
+++ b/NEWS
@@ -2,6 +2,13 @@ News for the tz database
Unreleased, experimental changes
+ Changes to future timestamps
+
+ Morocco's spring-forward after Ramadan is now predicted to occur
+ no sooner than two days after Ramadan, instead of one day.
+ (Thanks to Milamber.) The first altered prediction is for 2023,
+ now predicted to spring-forward on April 30 instead of April 23.
+
Changes to code
The undocumented and ineffective tzsetwall function has been
diff --git a/africa b/africa
index 724744f..5d3beb0 100644
--- a/africa
+++ b/africa
@@ -875,17 +875,30 @@ Zone Indian/Mauritius 3:50:00 - LMT 1907 # Port Louis
# https://maroc-diplomatique.net/maroc-le-retour-a-lheure-gmt-est-prevu-dimanche-prochain/
# http://aujourdhui.ma/actualite/gmt1-retour-a-lheure-normale-dimanche-prochain-1
#
-# From Paul Eggert (2020-04-14):
+# From Milamber (2020-05-31)
+# In Morocco (where I live), the end of Ramadan (Arabic month) is followed by
+# the Eid al-Fitr, and concretely it's 1 or 2 day offs for the people (with
+# traditional visiting of family, big lunches/dinners, etc.). So for this
+# year the astronomical calculations don't include the following 2 days off in
+# the calc. These 2 days fall in a Sunday/Monday, so it's not acceptable by
+# people to have a time shift during these 2 days off. Perhaps you can modify
+# the (predicted) rules for next years: if the end of Ramadan is a (probable)
+# Friday or Saturday (and so the 2 days off are on a weekend), the next time
+# shift will be the next weekend.
+#
+# From Paul Eggert (2020-05-31):
# For now, guess that in the future Morocco will fall back at 03:00
# the last Sunday before Ramadan, and spring forward at 02:00 the
-# first Sunday after the day after Ramadan. To implement this,
-# transition dates for 2021 through 2087 were determined by running
-# the following program under GNU Emacs 26.3.
-# (let ((islamic-year 1442))
+# first Sunday after two days after Ramadan. To implement this,
+# transition dates and times for 2019 through 2087 were determined by
+# running the following program under GNU Emacs 26.3. (This algorithm
+# also produces the correct transition dates for 2016 through 2018,
+# though the times differ due to Morocco's time zone change in 2018.)
+# (let ((islamic-year 1440))
# (require 'cal-islam)
# (while (< islamic-year 1511)
# (let ((a (calendar-islamic-to-absolute (list 9 1 islamic-year)))
-# (b (1+ (calendar-islamic-to-absolute (list 10 1 islamic-year))))
+# (b (+ 2 (calendar-islamic-to-absolute (list 10 1 islamic-year))))
# (sunday 0))
# (while (/= sunday (mod (setq a (1- a)) 7)))
# (while (/= sunday (mod b 7))
@@ -951,7 +964,7 @@ Rule Morocco 2021 only - May 16 2:00 0 -
Rule Morocco 2022 only - Mar 27 3:00 -1:00 -
Rule Morocco 2022 only - May 8 2:00 0 -
Rule Morocco 2023 only - Mar 19 3:00 -1:00 -
-Rule Morocco 2023 only - Apr 23 2:00 0 -
+Rule Morocco 2023 only - Apr 30 2:00 0 -
Rule Morocco 2024 only - Mar 10 3:00 -1:00 -
Rule Morocco 2024 only - Apr 14 2:00 0 -
Rule Morocco 2025 only - Feb 23 3:00 -1:00 -
@@ -967,7 +980,7 @@ Rule Morocco 2029 only - Feb 18 2:00 0 -
Rule Morocco 2029 only - Dec 30 3:00 -1:00 -
Rule Morocco 2030 only - Feb 10 2:00 0 -
Rule Morocco 2030 only - Dec 22 3:00 -1:00 -
-Rule Morocco 2031 only - Jan 26 2:00 0 -
+Rule Morocco 2031 only - Feb 2 2:00 0 -
Rule Morocco 2031 only - Dec 14 3:00 -1:00 -
Rule Morocco 2032 only - Jan 18 2:00 0 -
Rule Morocco 2032 only - Nov 28 3:00 -1:00 -
@@ -983,7 +996,7 @@ Rule Morocco 2036 only - Nov 23 2:00 0 -
Rule Morocco 2037 only - Oct 4 3:00 -1:00 -
Rule Morocco 2037 only - Nov 15 2:00 0 -
Rule Morocco 2038 only - Sep 26 3:00 -1:00 -
-Rule Morocco 2038 only - Oct 31 2:00 0 -
+Rule Morocco 2038 only - Nov 7 2:00 0 -
Rule Morocco 2039 only - Sep 18 3:00 -1:00 -
Rule Morocco 2039 only - Oct 23 2:00 0 -
Rule Morocco 2040 only - Sep 2 3:00 -1:00 -
@@ -999,7 +1012,7 @@ Rule Morocco 2044 only - Aug 28 2:00 0 -
Rule Morocco 2045 only - Jul 9 3:00 -1:00 -
Rule Morocco 2045 only - Aug 20 2:00 0 -
Rule Morocco 2046 only - Jul 1 3:00 -1:00 -
-Rule Morocco 2046 only - Aug 5 2:00 0 -
+Rule Morocco 2046 only - Aug 12 2:00 0 -
Rule Morocco 2047 only - Jun 23 3:00 -1:00 -
Rule Morocco 2047 only - Jul 28 2:00 0 -
Rule Morocco 2048 only - Jun 7 3:00 -1:00 -
@@ -1015,7 +1028,7 @@ Rule Morocco 2052 only - Jun 2 2:00 0 -
Rule Morocco 2053 only - Apr 13 3:00 -1:00 -
Rule Morocco 2053 only - May 25 2:00 0 -
Rule Morocco 2054 only - Apr 5 3:00 -1:00 -
-Rule Morocco 2054 only - May 10 2:00 0 -
+Rule Morocco 2054 only - May 17 2:00 0 -
Rule Morocco 2055 only - Mar 28 3:00 -1:00 -
Rule Morocco 2055 only - May 2 2:00 0 -
Rule Morocco 2056 only - Mar 12 3:00 -1:00 -
@@ -1031,7 +1044,7 @@ Rule Morocco 2060 only - Mar 7 2:00 0 -
Rule Morocco 2061 only - Jan 16 3:00 -1:00 -
Rule Morocco 2061 only - Feb 27 2:00 0 -
Rule Morocco 2062 only - Jan 8 3:00 -1:00 -
-Rule Morocco 2062 only - Feb 12 2:00 0 -
+Rule Morocco 2062 only - Feb 19 2:00 0 -
Rule Morocco 2062 only - Dec 31 3:00 -1:00 -
Rule Morocco 2063 only - Feb 4 2:00 0 -
Rule Morocco 2063 only - Dec 16 3:00 -1:00 -
@@ -1047,7 +1060,7 @@ Rule Morocco 2067 only - Dec 11 2:00 0 -
Rule Morocco 2068 only - Oct 21 3:00 -1:00 -
Rule Morocco 2068 only - Dec 2 2:00 0 -
Rule Morocco 2069 only - Oct 13 3:00 -1:00 -
-Rule Morocco 2069 only - Nov 17 2:00 0 -
+Rule Morocco 2069 only - Nov 24 2:00 0 -
Rule Morocco 2070 only - Oct 5 3:00 -1:00 -
Rule Morocco 2070 only - Nov 9 2:00 0 -
Rule Morocco 2071 only - Sep 20 3:00 -1:00 -
@@ -1063,7 +1076,7 @@ Rule Morocco 2075 only - Sep 15 2:00 0 -
Rule Morocco 2076 only - Jul 26 3:00 -1:00 -
Rule Morocco 2076 only - Sep 6 2:00 0 -
Rule Morocco 2077 only - Jul 18 3:00 -1:00 -
-Rule Morocco 2077 only - Aug 22 2:00 0 -
+Rule Morocco 2077 only - Aug 29 2:00 0 -
Rule Morocco 2078 only - Jul 10 3:00 -1:00 -
Rule Morocco 2078 only - Aug 14 2:00 0 -
Rule Morocco 2079 only - Jun 25 3:00 -1:00 -
@@ -1073,13 +1086,13 @@ Rule Morocco 2080 only - Jul 21 2:00 0 -
Rule Morocco 2081 only - Jun 1 3:00 -1:00 -
Rule Morocco 2081 only - Jul 13 2:00 0 -
Rule Morocco 2082 only - May 24 3:00 -1:00 -
-Rule Morocco 2082 only - Jun 28 2:00 0 -
+Rule Morocco 2082 only - Jul 5 2:00 0 -
Rule Morocco 2083 only - May 16 3:00 -1:00 -
Rule Morocco 2083 only - Jun 20 2:00 0 -
Rule Morocco 2084 only - Apr 30 3:00 -1:00 -
Rule Morocco 2084 only - Jun 11 2:00 0 -
Rule Morocco 2085 only - Apr 22 3:00 -1:00 -
-Rule Morocco 2085 only - May 27 2:00 0 -
+Rule Morocco 2085 only - Jun 3 2:00 0 -
Rule Morocco 2086 only - Apr 14 3:00 -1:00 -
Rule Morocco 2086 only - May 19 2:00 0 -
Rule Morocco 2087 only - Mar 30 3:00 -1:00 -
--
2.25.4
More information about the tz
mailing list