GEOS 3.2.2 should be fine. Cheers,
On Fri, Jun 25, 2010 at 12:52 PM, Emmanuel Lambert <[email protected]> wrote: > Hello Sean > > Thanks for you reply. I was also just about to add a follow-up comment. > > I upgraded my system to GEOS 3.2.2 (compile from source) and apparently > that solved the problem. So I guess it was an issue of libgeos. > Can I assume that Shapely 1.2.1 works fine with GEOS 3.2.2 ? > I experience no issues at this time, but would appreciate your feedback > on this. > > wbr > Emmanuel > > > On Fri, 2010-06-25 at 12:46 +0200, Sean Gillies wrote: >> 2010/6/24 Emmanuel Lambert <[email protected]>: >> > Hi, >> > >> > Attached is a list of polygons in WKT format. >> > I have a MultiPolygon consisting of these polygons. >> > >> > The cascaded_union function failes on this multipolygon. >> > "ValueError: No Shapely geometry can be created from null value" >> > >> > Script to reproduce the problem : >> > >> > from shapely.wkt import loads >> > from shapely.geometry import Polygon,MultiPolygon >> > from shapely.ops import cascaded_union >> > >> > f = open('MULTIPOLYGON.TXT','r') >> > polygons = [] >> > while True: >> > wkt = f.readline().replace("\n","") >> > print wkt >> > if len(wkt)==0: >> > break >> > pol = loads(wkt) >> > polygons.append(pol) >> > >> > mp = MultiPolygon(polygons) >> > up = cascaded_union(mp) >> > >> > I have tried several strategies to work around it, but cannot get to a >> > solution. Is this a bug in shapely, or is something wrong with my data? >> > Your advice would be appreciated. >> > >> > (Shapely 1.2.1) >> > >> > Thanks, >> > >> > Emmanuel >> > >> >> Hi Emmanuel, >> >> Before I try to reproduce this, can you run the script again and >> assert that each polygon is valid within the loop? >> >> pol = loads(wkt) >> assert pol.is_valid >> polygons.append(pol) >> > > > -- Sean _______________________________________________ Community mailing list [email protected] http://lists.gispython.org/mailman/listinfo/community
