|Bill Allombert on Fri, 4 Apr 2003 00:50:20 +0200|
[Date Prev] [Date Next] [Thread Prev] [Thread Next] [Date Index] [Thread Index]
|Re: polredabs() again|
On Fri, Apr 04, 2003 at 12:18:34AM +0200, Karim BELABAS wrote: > On the other hand, the current specification of polredabs is quite useless. > There's no application whatsoever for a "polynomial of absolute smallest > T2-norm". It's not even guaranteed to have minimal discriminant, or to > yield smallest coefficients. The only one I can see is to give a > pseudo-canonical representative for the field (this helps table builders, > less isomorphism tests...) I do not fully agree. Having a canonical defining polynomial is quite useful when you are generating lots of (small) isomorphic files (try galoisubfields on a large non abelian Galois groups). On the other hand, the polred specification that return a more or less random list of polynomials that may or may not map all subfields, and may or may not be smaller than the input, could benefit from an improvement. But anyway, it is just an interface issue. Cheers, Bill.