Natural neighbour interpolation method in raster

Hi jdh,

 

Holy cow! That one I did not understand how you did :-)

 

Anyhow I tried it now with my LIDAR data and it does not recognize the "_random_number" in the creation of the "_weightedValue" attribute.

 

What shall I do to fix this?

 

Best regards,

 

Jonas

 

 

The _random_number is an attribute storing the value you wish to interpolate (presumably Z). The thiessen polygons generated from the VoronoiDiagrammer need to have an attribute containing that value.

 

 

If your source data is a point cloud, you will need to either coerce the cloud into individual points, each containing the the Z value as an attribute prior to the VoronoiDiagrammer, or figure out a way to transfer the values to the thiessen polygons after generation.

 

 

In the AttributeCreator you need to change the _weightedValue expression to use the appropriate attribute name.

 

 

The workspace above was more a proof of concept than anything. I used this description of the algorithm to design the workspace:

 

The natural neighbors of any point are those associated with neighboring Voronoi (Thiessen) polygons. Initially, a Voronoi diagram is constructed of all the given points, represented by the olive-colored polygons. A new Voronoi polygon, beige color, is then created around the interpolation point (red star). The proportion of overlap between this new polygon and the initial polygons is then used as the weights.

 

 

 

http://desktop.arcgis.com/en/arcmap/10.3/tools/spatial-analyst-toolbox/how-natural-neighbor-works.htm

 

 

Good evening jdh,

 

I think I made the right modification but nothing comes out to the inspector.

 

See attached picture...What do I do wrong?

Best regards,

 

Jonas

Your Clipper-clipper need to be a polygon of the area of interest, not the individual points. A BoundingBoxReplacer, or BoundingBoxAccumulator would make one, depending on where in the workflow you place it.