Re: [Tzdist] Fun with tzdata and non-Gregorian DST rules

Jonathan Lennox <lennox@cs.columbia.edu> Fri, 13 November 2015 19:41 UTC

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Date: Fri, 13 Nov 2015 14:41:49 -0500
From: Jonathan Lennox <lennox@cs.columbia.edu>
To: Ken Murchison <murch@andrew.cmu.edu>
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Subject: Re: [Tzdist] Fun with tzdata and non-Gregorian DST rules
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On Friday, November 13 2015, "Ken Murchison" wrote to "Time Zone Data Distribution Service" saying:

> I briefly looked for other zones based on lunisolar calendars and didn't come
> up with any.  The Brazilian rules are essentially based around Easter and
> there is no way that I have found to represent Easter as a recurrence rule in
> iCalendar.

Between 2005 and 2012, Israeli daylight savings time (Asia/Jerusalem) ended
on the Hebrew calendar, which is lunisolar: the rule was that DST ended on
the Saturday before Yom Kippur (the 10th of Tishrei).  (It started on the
Gregorian calendar, on the Friday before April 2nd.)

The law was changed in 2013, but this still seems like something you could
try modeling with RSCALE, either for the historical period or for a
proleptic version of the 2005 rules.

-- 
Jonathan Lennox
lennox@cs.columbia.edu