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pombreda / pysal

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Bug in Kernel Weights when ArcDistance is Used #218

Closed GoogleCodeExporter closed 9 years ago

GoogleCodeExporter commented 9 years ago 
Kernel weights are not calculated correctly when Arc Distances are used.

In pysal.weights.Distance lines 314-317, the original point data is used to 
calculate the kernel function.  The problem is when ArcDistances are used the 
original point data are represented as 3d points on the unit sphere.  These 
points should not be used to calculate distances. All the distance calculations 
should be left to the KD-Tree so it can use the correct distance metric.

This bug causes erroneous results without issuing an error or warning, the fix 
should be rolled out in a point release.

Original issue reported on code.google.com by schmi...@gmail.com on 8 Aug 2012 at 5:22

GoogleCodeExporter commented 9 years ago 
Fixed in 1331

Original comment by schmi...@gmail.com on 8 Aug 2012 at 5:23