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inconsistent treatment of centroids in arc distance calculations in weights/user.py #219

Open GoogleCodeExporter opened 9 years ago

GoogleCodeExporter commented 9 years ago 
For distance based weights derived from a shapefile, arc distances are used if 
a radius value is passed in. otherwise euclidean distance is used. however, 
centroids for polygon shapefiles are obtained from trapezoidal decomposition 
(with an implicit euclidean assumption) so arc distances between these 
"centroids"  will not be equal to the arc distances between the spherical 
polygon centroids in cases where a radius value is passed in.

Original issue reported on code.google.com by sjsrey on 6 Sep 2012 at 3:16