topic Re: Kernel density of a set of points returns an empty raster in ArcGIS Spatial Analyst Questions

Kernel density of a set of points returns an empty raster

IuliaKlimina1 — Thu, 28 May 2015 10:05:45 GMT

Hello everyone

I'd like to calculate the Kernel density on a point shapefile. The shapefile is a result of a table with addresses that has been geocoded.

The Kernel Density tool is completed with a warning giving the following error:

000957 : Skipping feature(s) because of NULL or EMPTY geometry.

The resulting Kernel density is an empty raster.

I tried to resolve the error. I noticed that all records in the shapefile the field Shape* is completed as 'point' and no NULL values are to be found. I also tried to check the geometry (Data Management tools --> Features --> Check Geometry). This tool returned an empty table, meaning there were no issues found with the geometry.

Has anyone encountered this problem before? Any suggestions how to avoid it are welcome.

Thank you!

Re: Kernel density of a set of points returns an empty raster

DanPatterson_Retired — Thu, 28 May 2015 10:49:24 GMT

are you using projected data? What did you specify for the parameters in KernelDensity (in_features, population_field, {cell_size}, {search_radius}, {area_unit_scale_factor})

Re: Kernel density of a set of points returns an empty raster

curtvprice — Thu, 28 May 2015 15:56:26 GMT

I agree with Dan that is probably best practice to project your points to match your raster (especially if you are having issues). Then try the default parameters and see if you get anywhere.

Re: Kernel density of a set of points returns an empty raster

IuliaKlimina1 — Thu, 28 May 2015 16:04:13 GMT

The population field is set to NONE, cell size, search radius and area unit are left default.

After I checked the transformations for the data frame, with the same settings the return raster is no longer empty, but a density raster as expected.

However, the error message still stands.

Re: Kernel density of a set of points returns an empty raster

DanPatterson_Retired — Thu, 28 May 2015 16:12:03 GMT

doing it in the data frame isn't going to help...the data needs to be physically in a projected coordinate system, obtained by using the Project Tool in ArcToolbox, Data Management Tools, Projections and Transformations...Project

Re: Kernel density of a set of points returns an empty raster

IuliaKlimina1 — Fri, 29 May 2015 16:23:54 GMT

Dan, you are absolutely right!

I projected the data and the tool works perfectly now!

Thank you