I'm working with
I have a SpatialPolygonsDataFrame that has each row/Polygons list with only one Polygon. It also has an identifier column which I want to use to group by, and other attribute columns.
I would like to get the equivalent of group_by, where the attribute columns are aggregated, but where the corresponding Polygons' Polygon are concatenated in the same list.
Is there a function to do this?