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Bill Allombert on Thu, 30 Mar 2023 20:10:50 +0200
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- To: pari-dev@pari.math.u-bordeaux.fr
- Subject: Re: bit_ffs
- From: Bill Allombert <Bill.Allombert@math.u-bordeaux.fr>
- Date: Thu, 30 Mar 2023 20:09:14 +0200
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On Thu, Mar 30, 2023 at 07:02:34PM +0200, Ruud H.G. van Tol wrote:
>
> Might be interesting to add:
>
> https://en.wikipedia.org/wiki/Find_first_set
> https://www.man7.org/linux/man-pages/man3/ffs.3.html
> https://www.go4expert.com/articles/builtin-gcc-functions-builtinclz-t29238/
>
> Or are those too low-level?
>
> bit_ffs, bit_ctz
For the bitxxx functions family in GP,
you can use valuation(x,2) (resp. logint(x,2))
Cheers,
Bill.
- Follow-Ups:
- Re: bit_ffs
- From: "Ruud H.G. van Tol" <rvtol@isolution.nl>
- References:
- bit_ffs
- From: "Ruud H.G. van Tol" <rvtol@isolution.nl>