Issue: Group by on PointOnAreaOverlayer, LineOnAreaOverlayer

Hi @dmatranga, are you sure that the point (line) features and the area features have the Group By attribute with common name?

Hi @takashi, can you add more details to your answer. I am trying to understand how to use the group by in PointOnAreaOverlayer too and exeprience the same as @dmatranga.

The Group By option in those transformers will only perform the overlays for features that have the same values for the attribute(s) selected. It is as if you would set up a separate transformer for every unique combination of those selected attribute(s).

Thanks @redgeographics it is clearer for me now.

Not what I need. I have posted a question regarding my issue : https://knowledge.safe.com/questions/102372/count-points-in-area-based-on-an-attribute-value.html

Hey @takashi, the attributes for the points and areas do not have a common name.

Example:

• Takashi owns 12 homes (points) that fall within 3 areas (polygons), and there is an unknown quantity of homes within each of these 3 areas.
• Dan owns 8 homes (points) that fall within the same 3 areas (polygons), and there is an unknown quantity of homes within each of these 3 areas.

Point Data

Polygon Data

Sending to the PointOnAreaOverlayer to count how many houses Takashi and Dan have within each of the 3 areas, 'Group by' is set to 'Owner' and I expect the following result:

Does that kind of process work with the PointOnAreaOverlayer 'Group by'? Or am I missing something?

Don't set the Group By, but let the PointOnAreaOverlayer create a list on the areas, then use a ListHistogrammer (on the owner attribute) to get your end result.