[postgis-users] Simplify borders

[Andrea Peri]

>I'm sure this is a common problem, but I haven't been able to figure out how to do it in PostGIS.
>I want to simplify a representation of borders.  Specifically, we have divided an area into "zones", and
>we currently have a polygon* for each zone.  The zones cover 100% of the "region", i.e. they divide the "region."
>The whole region is divided into zones.
>The polygons are stored independently, as a polygon geometry.  My first question is how to ensure the border
>of one polygon matches the border of the adjacent polygon?  That is, there should be no overlap
>or underlap (slivers).  I think there's a system with buffering (to remove underlap a.k.a. slivers) and
>then ST_Intersection (to remove overlap).  But I'm not sure of the right sequence or if there's a better system.
>Isn't there a geometry class (or something) that stores the border once instead of for each polygon separately?

Hi,

I think you are speaking of the topology.

There is available a topology extension for postgis in the svn.

-- 
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Andrea Peri
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qwerty àèìòù
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