[EMAIL PROTECTED] pisze:
1) How to get "just the outline" of the island ? Both v.type and v.extract with "type=boundary,line" produce an empty vector.
The manual reads: --- NOTES Only features with a category number will be extracted. So if you want to extract boundaries (which are usually without category, as that information is normally held in the area's centroid) you must first use v.category to add them. ---
2) The main issue is to derive all counties of the island which lie on the shore (= ignore the counties which don't have a beach). How can a topological query be set up, saying "derive all the county polygons which share a common boundary with the islands shoreline" ?
You might try v.to.db opt=sides col=left,right. After that select those areas, of which at least one boundary only has 'left' or 'right' populated. Maciek -- Maciej Sieczka www.sieczka.org _______________________________________________ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user