Re: another angle os

[Karim BELABAS <Karim.Belabas@math.u-psud.fr>]

On Wed, 5 Mar 2003, Igor Schein wrote:
> ? setrand(7);rnfkummer(bnrinit(bnfinit(quadpoly(-391483,y)),2,1),Mat(3))
>   ***   inconsistent data in hnfdivide.

Our old friend the heuristic class group bound: [ first item in TODO ]

(20:49) gp >  setrand(7);bnfinit(quadpoly(-391483,y),,[0.4]).cyc
%1 = [64]    \\ correct
(20:50) gp >  setrand(7);bnfinit(quadpoly(-391483,y),,[0.3]).cyc
%2 = [32, 2] \\ wrong

> How let's look at the timing pattern:
[...]
> So except .3, all other values produce a valid answer, but some more
> efficiently, some less efficiently, and the timing is consistent
> within each of the 2 groups.  Luck factor?

I don't have any other explanation.

    Karim.
-- 
Karim Belabas                     Tel: (+33) (0)1 69 15 57 48
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