ruranges-core

Pure Rust core interval algorithms for the ruranges Python extension.

The crate is deliberately dataframe-agnostic: everything here takes and returns plain slices, so both pyranges1 (pandas) and polaranges (polars) can build on it without either dataframe library appearing in the dependency tree.

Most modules are interval algorithms — overlaps, nearest, merge, cluster, complement, subtract, tile, split. Two are the sort pipeline, and are worth calling out because they are shared specification, not just shared code:

• sorts — sort_order_idx computes the row order for a sort by (group, start, end) with optional per-row direction reversal. Three stable LSD radix passes.
• ranks — natural_rank / lexical_rank turn a key column's distinct string values into ascending integer codes, and fold_ranks collapses several coded keys into the single group argument sort_order_idx takes.

ranks::natural_cmp is the definition of natural ordering (chr2 < chr10 < chrM) for every library built on ruranges. It lives here rather than in each of them so the same data cannot sort two ways; the unit tests check it against expectations produced by Python's natsort 8.4.0, and document the two places the two deliberately differ (Unicode normalisation, non-ASCII digits).

cargo test