#11890: Sage cannot factor polynomials over number fields with unfactorable
discriminant
-----------------------------+----------------------------------------------
   Reporter:  jdemeyer       |          Owner:  davidloeffler               
       Type:  enhancement    |         Status:  new                         
   Priority:  major          |      Milestone:  sage-4.7.2                  
  Component:  number fields  |       Keywords:  nffactor PARI nfinit pari_nf
Work_issues:                 |       Upstream:  N/A                         
   Reviewer:                 |         Author:                              
     Merged:                 |   Dependencies:                              
-----------------------------+----------------------------------------------
Description changed by jdemeyer:

Old description:

> Let `K` be a number field with a discriminant which cannot be factored.
> Let `f` be a polynomial in `K[x]`.  Then Sage is unable to factor `f`
> because it calls PARI's `nfinit()` on `K`:
> {{{
> sage: p = next_prime(10^50); q = next_prime(10^51)
> sage: K = QuadraticField(p*q)
> sage: x = polygen(K); factor(x^2+1)
> }}}

New description:

 Let `K` be a number field with a discriminant which cannot be factored.
 Let `f` be a polynomial in `K[x]`.  Then Sage is unable to factor `f`
 because it calls PARI's `nfinit()` on `K`:
 {{{
 sage: p = next_prime(10^50); q = next_prime(10^51)
 sage: K = QuadraticField(p*q)
 sage: x = polygen(K); factor(x^2+1)
 [... takes a very long time ...]
 }}}

 The solution is to avoid calling `nfinit()`.

--

-- 
Ticket URL: <http://trac.sagemath.org/sage_trac/ticket/11890#comment:1>
Sage <http://www.sagemath.org>
Sage: Creating a Viable Open Source Alternative to Magma, Maple, Mathematica, 
and MATLAB

-- 
You received this message because you are subscribed to the Google Groups 
"sage-trac" group.
To post to this group, send email to [email protected].
To unsubscribe from this group, send email to 
[email protected].
For more options, visit this group at 
http://groups.google.com/group/sage-trac?hl=en.

Reply via email to