bpo-37295: More direct computation of power-of-two factor in math.comb #30313
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I'm not sure how. Can you elaborate? We could use a lookup table for small values in the popcount implementation, but I'm not sure it's worth changing. |
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We could use the same lookup table in the popcount implementation for For #30305 I will need to extend the table to 127. |
serhiy-storchaka
reviewed
Dec 31, 2021
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
…math-comb-zero-counts
serhiy-storchaka
approved these changes
Dec 31, 2021
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This PR replaces the current popcount-based code for computing the largest power of two dividing math.comb(n, k) (for small n) with a more direct method based on counting trailing zeros of the factorials involved. See the issue for further discussion.
https://bugs.python.org/issue37295