Re: polredabs failure

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

On Thu, 9 Oct 2003, Igor Schein wrote:
> ? p1=x^16-4*x^15-20*x^14+80*x^13+138*x^12-712*x^11+736*x^10+1200*x^9-8138*x^8+9288*x^7+1904*x^6-25248*x^5+73988*x^4-19184*x^3+41192*x^2+69456*x+30724;
> ? p2=x^16 + 66*x^12 + 3627*x^8 + 48114*x^4 + 531441;
> ? p1==polredabs(p1)
> 1
> \\ p1 already *reduced*
> ? poldegree((v=polcompositum(p1,p2))[#v])
> 16
> \\ isomorphic
> ? norml2(polroots(p1))
> 91.81780460041328907655758261
> ? norml2(polroots(p2))
> 87.63560920082657815311516524
> \\ so we should have polredabs(p1)==p2

A complicated typo. The smallest element was found, then deleted due to a typo
which assessed to it the norm of another (larger) element, during the
"Sorting" phase (when there are too many small vectors, the list overflows,
and we need to discard some of them). Fixed in CVS.

Cheers,

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