Polars Releases the GIL Before It Does Any Real Work
Every public py-polars entry point wraps its work in enter_polars, which calls pyo3’s Python::detach to drop the GIL. The GIL is re-acquired with Python::attach at exactly one …
Polars
Polars Estimates Cardinality With HyperLogLog
The HyperLogLog register trick turns a 64-bit hash into an index and a rank, and Polars’ estimator replaces the classic bias correction with Ertl’s tau/sigma correction; a second, …
Polars Finds the Top K With a Bounded Heap
The streaming engine keeps one BinaryHeap of k keys per pipeline, admits a key only if it is strictly below the current threshold, merges the per-pipeline heaps pairwise at the …
Polars Sorts Floats the Way Nobody Wants Them Sorted
TotalOrd is Polars’ own total order for floats: all NaNs compare equal and NaN is the maximum, -0.0 and 0.0 are indistinguishable, and hashing canonicalises both so equality and …
Polars Parses JSON Without Building a DOM
Polars’ JSON reader parses a line into simd-json borrowed values that point into the source buffer, then pushes each field into the matching column builder; no DOM is allocated and …