Karim BELABAS on Mon, 22 Sep 2003 14:02:41 +0200 (MEST)


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Re: rnfpolred bug


On Mon, 15 Sep 2003, Bill Allombert wrote:
> It seems that rnfpolred has a bug when used with bnf:
>
> ? rnfpolred(nfinit(polcyclo(3,a)),x^3-19);
> time = 30 ms.
> ? rnfpolred(bnfinit(polcyclo(3,a)),x^3-19);
>   ***   user interrupt after 1mn, 41,460 ms.

A typo when computing the relative T_2 matrix (missing conjugate), which ends
up not being positive [ so that precision problem is detected --> oo loop ]

Fixed in CVS.

    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/
F-91405 Orsay (France)            http://www.parigp-home.de/  [PARI/GP]