Iran's exact law for re-instating daylight saving

Andy Lipscomb AndyLipscomb at
Wed Nov 7 18:27:21 UTC 2007

That is correct; calculating dates by the Persian calendar requires astronomical computations. (Israel also uses its native calendar in establishing DST dates, IIRC, but the Jewish calendar is computable with simple math.)
Unless/until it can be assumed that computers have the capacity to compute these calendars, we probably have to just extend out a schedule of dates, but with enough data in comments that coders working with systems that do have that capacity can substitute a proper computation.

J Andrew Lipscomb, CPA•ABV, ASA 

Decosimo Corporate Finance 

900 Tallan Building 
2 Union Square 
Chattanooga, TN 37402 
Fax 423.266.6671 



From: Paul Schauble [mailto:Paul.Schauble at] 
Sent: Wed 7 November 2007 09:06
To: tz at
Subject: Re: Iran's exact law for re-instating daylight saving

I think there. Is an additional complication here. I believe the Persian calendar begins on the day of the true equinox. This varies over about a 2 day period so there is not a fixed correspondence between Persiam dates and Gregorian.

I'm sure I will be corrected if need be.


----- Original Message -----
From: Roozbeh Pournader <roozbeh at>
To: Paul Eggert <eggert at CS.UCLA.EDU>
Cc: tz at <tz at>
Sent: Wed Nov 07 05:09:15 2007
Subject: Re: Iran's exact law for re-instating daylight saving

On Tue, 2007-11-06 at 00:27 -0800, Paul Eggert wrote:
> Thanks for the citation.  That "24 hours" worries me a bit; it's not
> clear to me whether it means midnight at the start or at the end of
> the day.

It's the midnight at the end of the day.

> Just to double check, are the current transitions OK?

Yes. The law is basically reinstating the 1991 regulation of President
Rafsanjani's board of ministers which was canceled by President
Ahmadinejad's board of ministers a few days before daylight saving was
supposed to come into effect again in 2006.

BTW, the funny thing is that Hassan Habibi, the First Vice President
that signed the 1991 regulation, and Gholam Ali Haddad-Adel, the
Parliament's Speaker who signed the 2007 one, have been the only two
presidents of Iranian Academy of Persian Language and Literature since
its revival in 1990. Habibi became the Academy's President when it was
recreated (while also serving as First Vice President) and was replaced
by Haddad-Adel after his term finished. But later, Haddad-Adel resigned
from the post when he became the Parliament's Speaker, leading in Habibi
filling his original position again.


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <>

More information about the tz mailing list