FW: FW: Corrections to historic German timezone information

Paul Eggert eggert at CS.UCLA.EDU
Fri Feb 8 20:14:02 UTC 2008

"Markus Scherer" <markus.icu at gmail.com> writes:

> All of France, and Paris, was occupied. It makes sense to apply the
> occupier's rules that were in effect there during the occupation.

Our sources report that Vichy France used different DST rules than
German-occupied France did.  The "France" rules are for Vichy France.
Europe/Paris uses the occupied-Europe rules; Europe/Monaco (not part
of Vichy, but reportedly used Vichy rules) uses the French rules.

> In Berlin there were multiple occupiers. The eastern sector [2] was
> smaller and less populous than the three western ones together [1].

The tz database uses a single latitude/longitude coordinate to
identify a city by its center; the current format does not have the
capability to represent the entire city outline.  So the question,
from the tz point of view, is: what is the center of Berlin?  If it's
in east Berlin the tz database uses the rules appropriate for that
location.  Currently the database simply accepts Shank & Pottenger's
definition for the center of Berlin (as being in east Germany) but if
that's incorrect then we can fix it.

> Should the TZ rules not reflect the transitions in the larger part of
> the territory, for historical data where the TZ database won't split
> the time zone to describe each of the parts?

Not the way it's currently constructed.  It currently specifies one
location for each zone, and gives accurate data for that location.

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