This question is similar to a previous post where the member asked if it were possible to create Theissen (Voronoi) polygons from lines:

Creating Thiessen (Voronoi) polygons using lines (rather than points) as the input features?

The issue I'm trying to resolve is that I have hundreds of thousands of point features that belong to an assigned territory by clerks who may or may not be familiar with the geography of these areas. As such, many points get assigned the wrong territory value. In order to fix this, I want to find points that don't belong within a cluster and generate polygons from the points that are aligned with streets. If a street dead ends then I want the voronoi polygon to end when it meets the edge of the closest point's voronoi polygon. Once I am confident that the territory boundaries have been accurately defined, I would like to perform a spatial join and carry over the polygon territory values to the point features.

I grasp that the best approach is to convert the polygons and line features to raster in order to increase precision of Voronoi cell boundaries (although I could be totally wrong on this).

The only difference is that I want to create Voronoi polygons from point features but want the boundaries to stop when they encounter the boundary generated from another point within the feature class as well as a line feature.

This is what I want to fix so that the polygon boundaries do not cross the line:

enter image description here

I used QGIS to create the Voronoi polygons because I don't have the license level to create Thiessen polygons in ArcGIS. I haven't seen an option to use a barrier in create Voronoi polygons in QGIS.

I brought the features in from QGIS to ArcMap to use features to raster tool and got this:

enter image description here

I'm not sure where to go from here.

| improve this question | | | | |
  • I think you need to think about what you are trying to achieve a bit more. You want to constrain the polygons by lines; however a number of those lines stop, not connected to anything. So in those situations how are those lines supposed to constrain the voronoi polygons - what are the rules around that? – Liam G Dec 22 '16 at 3:41
  • +1 to that comment, also what is the real-world use-case here? It seems to be something people want, but it's a seemingly obscure technical operation, e.g. see gis.stackexchange.com/questions/144210/… I think it's obscure in Voronoi technicalities, wherea in Delaunay triangulation it's not at all obscure to want to include input lines (but then it's not technically Delaunay any more). – mdsumner Dec 22 '16 at 5:03
  • Could you fake it by cutting all the voronoi polygons with the boundary lines, and only keep the pieces that intersect with the input points? (It'll be ambiguous when the point and line intersect already). If you could explain why this needs to happen, and whether the discarded parts of the cells are important or not, I think that would help. – mdsumner Dec 22 '16 at 5:03
  • @Freight_Train I am working on a process to correct territory assignments. Clerks often assign customers to the wrong service type so I want to create a polygon with the correct service value in the attribute table that will be used in a spatial join to correct any service values erroneously assigned to customers. There are thousands of theses territories so I was hoping I could use voronoi generation. When there is no line barrier the vornoi would continue until it encountered the edge of the closest other voronoi. – geoJshaun Dec 22 '16 at 20:17
  • @mdsummer I edited my question with more elaboration on what I'm trying to achieve. – geoJshaun Dec 22 '16 at 21:45

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.