Order-invariant geometry fingerprint of a zone layer

Hashes each feature's WKB, ordered by the zone key (not by row order), so a layer re-saved with features shuffled fingerprints identically while any real change to a boundary does not.

Usage

zone_geom_hash(x, key_col = NULL, zone_type = NULL, layer = NULL)

Arguments

x

an sf object, or a path to a vector file (e.g. .gpkg)

key_col

column holding the zone key; resolved from zone_type when given, else the first column whose name ends in key, else row order

zone_type

when given, resolves key_col via zone_key_col() — the correct choice when a layer carries several *_key columns

layer

layer name when x is a multi-layer file (default: the first)

Value

a list with n, key_col, keys and a 16-char geom_hash