[tz] tz dependency lat & lng

Guy Harris guy at alum.mit.edu
Thu Sep 5 19:47:53 UTC 2013


On Sep 5, 2013, at 12:30 PM, Lester Caine <lester at lsces.co.uk> wrote:

> Zoom in on http://maps.derickrethans.nl/?l=timezone,timezones&lat=52.485&lon=-1.890&zoom=4 the entire database of shape files needs to be replaced with the administrative boundaries from the OSM database,

To which *level* of administrative boundary are you referring?

	http://wiki.openstreetmap.org/wiki/Tag:boundary%3Dadministrative

Level 2 (nation-state boundaries) is obviously insufficient to handle the entire tzdb, and going down to, for example, the US's level 8 ("municipalities, including cities, villages, etc. Also incorporated townships (New Jersey, Pennsylvania.)") is equally obviously overkill in most cases.

In order to use OSM to construct boundaries for tzdb zones, a *mixture* of administrative boundaries would be required, so that *wouldn't* constitute replacing tzdb boundaries with administrative boundaries from the OSM database, it would constitute *constructing* higher-quality tzdb boundaries from the administrative boundaries.


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