Assign or reconcile hierarchical codes

Assign a fresh hierarchical code to a flat, uncoded layer, or reconcile an already-coded layer against a new uncoded candidate.

Cold-starting a code on a layer with no existing convention, code-refactor ranks each level's units under their parent and assigns a fresh sequential code in your own format:

topo-tools code-refactor admin2.geojson admin2_coded.geojson \
  --root-code AFG --delimiter . --min-width 3

Reconciling an already-coded OLD layer against an uncoded NEW candidate (a new delivery of the same boundary), code-update classifies every unit (the same engine change uses) and retains, replaces, or retires each code per that classification, cascading a changed parent's new code prefix down to its unchanged/renamed descendants. Format is auto-detected off OLD's own codes unless overridden:

topo-tools code-update admin1_old.geojson admin1_new.geojson

Add --link-by-code (plus --code-column-a/--code-column-b) if both layers share a separate stable source identifier, to link a relocated unit that spatial overlap alone would misclassify.

See code-refactor reference, code-update reference, and the shared code explanation page for the code format and retention policy.