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Can you help me break down shape A to different linestrings: lines 2 & 3 AND line 1? The shape contains three different polygons (A, B, C). I wish to determine the start/end point of each part with the common points of the other polygons.

I'm using Postgis 1.5 / Python Shapely


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up vote 0 down vote accepted

The intersection of A and B's exterior rings will be your segment 3, yes?

line3 = a.exterior.intersection(b.exterior)

Does that help?

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thanks! it did. line3 = a.boundary.intersection(b.boundary) – OLS Jul 4 '13 at 17:30

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