Kernel Density Empty Geometry

Question

Hello,

I'm trying to do a Kernel Density on point data but it keeps saying there is a 'general function failure' and that 'the operation was attempted on an empty geometry'. It has worked on previous point data but now I'm at a loss. Does anyone know what might cause this and how to fix it?

Thank you.

DerekNelson · Answer

If you want to leave the default search radius and just make a smaller cell size you can get a smoother (less pixelated) result....depending on your resolution I would try multiple sizes... i.e. .001 (really small)

CharmaineRice · Answer

If you are using map coordinates to specify the kernel, double check what the output coordinate system is set to. For example, 3 x 3 degrees is a pretty big kernel!

Hi, thanks for the reply,

I'm not sure what you mean but I was doing the Kernel with the point layer selected as the extent and was using metres to specify the search area (hope I'm using the right words, I don't have access to the ArcGIS at the moment). I think I'd made my search area larger than the area of the layer, whereas the first time I was shown the display was used as the extent so could have been a much larger area, so that might have been what was going wrong! I'll have another go!

curtvprice · Answer

Maybe I was using too large a search radius for the size of the layer, though when I was originally shown how to do it on the same data much larger numbers were used!

If you are using map coordinates to specify the kernel, double check what the output coordinate system is set to. For example, 3 x 3 degrees is a pretty big kernel!