# point feature to raster with count of unique points

I am using ArcGIS 10.1 with Python 2.7 I have a point layer with thousands of points that each hold an id value of its owner. One owner can have multiple points, meaning that points can have the same owner_id. I want to create a raster that counts the number of unique owner_ids in each cell.

Is there a way to create a raster with a value containing the count of unique owner_ids? In other words, I want a raster with the number of unique owners instead of a raster with the number of points in each cell.

I have tried creating separate raster grids for each individual owner and its points (found it somewhere on another forum), but since my data in total is more than a million different owner_ids, this will take way too long.

• @Aaron, My owner_ids range from 1 to about 1 million (and are integers). If I select range in point to raster, a value of 0 means 1 unique owner_id and a value between 1 and 1 million means at least 2 unique owner_ids, but then still I don't know how many unique owner_ids per cell
– Koen
Jan 7, 2015 at 14:51
• there is something on the esri forum, where a possible workaround is mentioned, although i can't folow Bill Huber's method as explained in the last comment on this post: forums.esri.com/Thread.asp?c=93&f=995&t=199401
– Koen
Jan 7, 2015 at 18:15

Here is what I would do.

1: You should create a raster (a constant raster could do it) with the cell size you want.

http://pro.arcgis.com/fr/pro-app/tool-reference/spatial-analyst/create-constant-raster.htm

2: You convert that raster to polygons.

http://pro.arcgis.com/fr/pro-app/tool-reference/conversion/raster-to-polygon.htm

3: Make sure you have an unique identifier for each cell (there should be an FID) else create it with field calculator.

4: Make a Spatial Join where you sum up the points in each polygons.

http://pro.arcgis.com/fr/pro-app/tool-reference/analysis/spatial-join.htm

5: Convert the resulting polygons to points.

http://pro.arcgis.com/fr/pro-app/tool-reference/data-management/feature-to-point.htm

6: Then convert these points to a raster.

http://pro.arcgis.com/fr/pro-app/tool-reference/conversion/point-to-raster.htm

The spatial join will take some time as ArcGIS uses the calculate field function and it is really not optimized for huge database. But i think the whole process will work nicely. You could use the model builder if it is a recuring process.