I need to create Thiessen Polygons from a line file ?

Question

Im looking for a way or workflow to create Thiessen Polygons from a Line file

MatthewLeonard · Answer

OK, then I'm thinking that if the attribute I need from the lines is carried over to the points and then to the polygons that are generated from the points...then I will be able to dissolve the Thiessen polygons by that attribute and that will give me the result I need.  This would be nice if it works... Thanks!

DanPatterson_Retired · Answer

They should be single part features, multiparts will either fail as inputs or they will be exploded.  As well, you should remove duplicate points (ie points shared by polygons).  Thiessen Polygons (as are Voronoi diagrams, Delaunay triangulations, TINS and other spatial delination methods) are all about the points not your attributes... you will deal with that through spatial associations done after the fact.

You might also want to try a small sample to see if you get the triangulation you want first

MatthewLeonard · Answer

I'm considering trying this technique.  But I'm wondering this... I want to create one polygon for each group of lines that share an attribute.  When I convert the lines to points, I'll end up with multiple points that represent each line...and I'm thinking I should dissolve those points into multi-part point features based on the attribute I'm interested in.  But the Create Thiessen Polygons tool creates one polygon for each input point...so how does it handle multi-part point features?  I don't see this addressed on the help page for the tool.  Does it create one polygon for each point within a multi-part feature, or create one polygon for the entire multi-part feature?  I suppose I could try it and find out, but that may take a while since I have a large data set.