sjoin one-to-one option if intersection overlaps several polygon

I have a grid poly (qk) which I want to join attributes from admin boundaries (ph). For each poly in qk I want to take attributes of the first located feature in ph I (one-to-one).

I can’t find an ption in sjoin to do this, instead it always (one-to-many).

See example code here and viz in QGIS below:

[brendan-ward]

@cyrchi you can first do sjoin_nearest then apply additional predicates to the pairs of geometries from your source and target data frames to further filter the results to remove those that only intersect at the boundary, or use a centroid (or some other representative geometry) of your source and target geometries and take the one with the least distance per source (left) geometry.

We’d have to develop additional functionality at a lower level (i.e., shapely) to get at the concept of joining to nearest but not overlapping geometries, if that is a common activity to be doing with sjoin_nearest.

[Greenall]

@martinfleis Looking at your implementation I’m sure it is faster. Was not aware of query_bulk.

notice you don’t do any CRS transformation within the method but guess that’s actually the right call since if you are not using projected CRS then geopandas will raise anyway.

Tobler looks like a useful lib - wasn’t aware of it before - thanks