REF: Release gil in is_range_indexer, is_sequence_range

[mroeschke]

Just to be polite.

[jbrockmendel]

Does this affect anything? IIUC releasing and reacquiring is not zero-cost

[mroeschke]

Does this affect anything? IIUC releasing and reacquiring is not zero-cost

Minor help for users that want to multi-threading things with pandas (e.g. Dask). Other helper functions in this file release the gil if possible. It appears there's some overhead; in this worst case with small data

In [1]: import pandas as pd

In [2]: import numpy as np

In [3]: arr = np.array([0, 1])

In [4]: %timeit pd._libs.lib.is_range_indexer(arr, 2)
503 ns ± 2.63 ns per loop (mean ± std. dev. of 7 runs, 1,000,000 loops each)  # PR
466 ns ± 7.35 ns per loop (mean ± std. dev. of 7 runs, 1,000,000 loops each)  # main

[jbrockmendel]

Thanks @mroeschke