Karim BELABAS on Fri, 07 Nov 2003 12:48:02 +0100


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Re: Experimenting with the Alpha build. 

On Fri, 7 Nov 2003, Bill Allombert wrote:
>>> I also recompiled GMP with -ffast-math too for the test. In theory GMP might
>>> perform some FP maths (FFT multiplication? or is it NTT?).
>>
>> NTT from a quick glance at the code. I don't think GMP uses doubles much,
>> either. mp_limb_t is always a variant of some unsigned integer (int, long,
>> long long).
>
> What is NTT ? GMP FFT use modular arithmetic, not double.

Number Theoretic Transform, aka modular FFT, etc.

    Karim.
-- 
Karim Belabas                     Tel: (+33) (0)1 69 15 57 48
Dép. de Mathématiques, Bât. 425   Fax: (+33) (0)1 69 15 60 19
Université Paris-Sud              http://www.math.u-psud.fr/~belabas/
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