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Karim Belabas on Thu, 09 Mar 2023 17:00:47 +0100
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- To: Max Alekseyev <maxale@gmail.com>
- Subject: Re: logint() bug?
- From: Karim Belabas <Karim.Belabas@math.u-bordeaux.fr>
- Date: Thu, 9 Mar 2023 16:59:13 +0100
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* Max Alekseyev [2023-03-09 12:08]:
> I'd assume logint(x,b) is just an accurate implementation of
> floor(log(x) / log(b) )
It's not. Apart from the obvious special case b = 2 (where we use exponent()),
logint uses an all-integral binary splitting method to compute the bits
of e = logint(x,b) one by one.
Cheers,
K.B.
--
Pr Karim Belabas, U. Bordeaux, Vice-président en charge du Numérique
Institut de Mathématiques de Bordeaux UMR 5251 - (+33) 05 40 00 29 77
http://www.math.u-bordeaux.fr/~kbelabas/
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