In ArcGISOnline, I can create a 20-min drive time polygon on a point location, then do a 'Aggregate Data / Summarize Within' analysis on that 20-min drive-time polygon and another layer that is an aggregation of data at a zipcode level aggregated at a blockgroup level.
My understanding is that the 'Summarize Within' analysis does a proportional calculation for any data where the drive-time polygon intersects the underlying block group as show in the attached figure.
Is it possible to do a similar 'spatial aggregation' query in JavaScript that does a proportional calculation for intersecting polygons, as show in attachment?
If possible, can you point to any example code? I would imagine that an aggregated analysis may take some time. Is there an async JavaScript function that could accommodate this?