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API reference

All public H3 operations return Polars expressions and can be used in select, with_columns, and lazy queries. Functions accept column names or Polars expressions unless their signature documents a scalar argument.

Family Purpose Reference
Indexing Convert coordinates, cells, local IJ coordinates, and boundaries. Indexing
Geometry Tile WKT/WKB polygons and dissolve cell sets into WKT. Geometry
Index inspection Validate, convert, and inspect H3 indexes. Index inspection
Hierarchy Navigate parent/child relationships and compact cell sets. Hierarchy
Directed edges Create and inspect edges between neighboring cells. Directed edges
Traversal Measure grid distance and construct rings, disks, and paths. Traversal
Vertices Create, validate, and locate H3 vertices. Vertices
Metrics Calculate areas, lengths, distances, and global cell counts. Metrics

For optional Folium helpers, see the separate graphing reference.

Geometry representation

Geometry conversion accepts ordinary WKT String or WKB Binary columns. Geometry values exist only inside the Rust expression, so no Polars geometry dtype is required.