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Author mark.dickinson
Recipients lschoe, mark.dickinson, pablogsal, rhettinger, skrah, steven.daprano, tim.peters
Date 2019-02-19.15:32:02
SpamBayes Score -1.0
Marked as misclassified Yes
Message-id <1550590322.49.0.739872280444.issue36027@roundup.psfhosted.org>
In-reply-to
Content 
> it's still a bit subtle that you have to use pow(a, -1,p) instead of pow(a, p-2, p) to let the modular inverse be computed efficiently

That's not 100% clear: the binary powering algorithm used to compute `pow(a, p-2, p)` is fairly efficient; the extended gcd algorithm used to compute the inverse may or may not end up being comparable. I certainly wouldn't be surprised to see `pow(a, p-2, p)` beat a pure Python xgcd for computing the inverse.
History
Date User Action Args
2019-02-19 15:32:02mark.dickinsonsetrecipients: + mark.dickinson, tim.peters, rhettinger, steven.daprano, skrah, pablogsal, lschoe
2019-02-19 15:32:02mark.dickinsonsetmessageid: <1550590322.49.0.739872280444.issue36027@roundup.psfhosted.org>
2019-02-19 15:32:02mark.dickinsonlinkissue36027 messages
2019-02-19 15:32:02mark.dickinsoncreate