fix for issue #291 -- ensure very short edges are not inset to NaN values -- just return null and ignore them
fix for issue #291 -- ensure very short edges are not inset to NaN values -- just return null and ignore them

Brunel-Visualization/Brunel,Brunel-Visualization/Brunel,Brunel-Visualization/Brunel,Brunel-Visualization/Brunel,Brunel-Visualization/Brunel,Brunel-Visualization/Brunel