Relational keys and geometry
Deterministic keys, ranking and grouping for relational index sets, and the polygon geometry used by regridding.
| Operation | Kind | Bindings | Summary |
|---|---|---|---|
area_tolerance_ok | function | Python, Rust | Combined rel+abs area-agreement gate with a sliver floor (B.5 / §5.8.2). |
distinct | function | Python, Rust | Set semantics over rows: sort by the §5.5.1 total order, then drop |
group_aggregate | function | Python, Rust | Group-by + semiring aggregate (rule 5). |
intersect_polygon | function | Python, Rust | Clip two lon-lat polygon rings; return the overlap ring (RFC §8.1). |
polygon_area | function | Python, Rust | Reference (unsigned) area of an overlap ring under manifold. |
rank | function | Python, Rust | Dense integer renumbering (rule 3): assign IDs by position in the sorted distinct sequence. |
skolem | function | Python, Rust | Canonical-tuple Skolem key (rule 4). |
skolem_edge | function | Python, Rust | Canonical key for an undirected pair (a symmetric relation): (min(a, b), max(a, b)). |
ranking | type | Python, Rust | Result of rank. |
float_key_error | error | Python, Rust | Raised when a relational key contains a floating-point component. |
geometry_error | error | Python, Rust | A polygon-clip / area evaluation failed (bad operand, degenerate input). |