Thank you...I'm wrong.  Yes, prime_divisors gives the number of
distinct prime divisors (just like the name says).

NS



On Mar 9, 4:24 pm, William Stein <[email protected]> wrote:
> On Mon, Mar 9, 2009 at 2:21 PM, Noel <[email protected]> wrote:
>
> > Thank you all for your replies!  Now I have another problem:
>
> > sage: for f in list(GF(2)['x'].polynomials(of_degree=2)):
> > ....:     print len(prime_divisors(f)), f
> > ....:
> > 1 x^2
> > 1 x^2 + 1
> > 2 x^2 + x
> > 1 x^2 + x + 1
>
> > Only one of these polynomials should have a 1 in the first column (the
> > polynomial that's irreducible).  What am I doing wrong?
>
> Why do you think len(prime_divisors(x^2)) should be 2?   It's 1 since
> x^2 has only one prime divisor.
>
> William
>
>
>
>
>
> > Thanks,
> > NS
>
> > On Mar 9, 1:20 pm, John Cremona <[email protected]> wrote:
> >> On 9 Mar, 18:05, YannLC <[email protected]> wrote:
>
> >> > On Mar 9, 6:38 pm, Nick Alexander <[email protected]> wrote:
>
> >> > > On 9-Mar-09, at 8:48 AM, Noel wrote:
>
> >> > > > Hello Y'all,
>
> >> > > > What's the best way of listing all polynomials of a given degree with
> >> > > > coefficients in a finite field?
>
> >> > > If you want a one liner, you could use
>
> >> > > sage: [ GF(3)['x'](list(t)) for t in  (GF(3)^2) ]
> >> > > [0, 1, 2, x, x + 1, x + 2, 2*x, 2*x + 1, 2*x + 2]
>
> >> > > Nick
>
> >> > if you want another one liner, and an exact degree, you could use
>
> >> > list(GF(3)['x'].polynomials(of_degree=2))
>
> >> That is better since (without the list) it is an iterator;  also you
> >> can put in max_degree= instead of of_degree= to get all polys up to a
> >> given degree.  Someone else must have needed this and implemented it!
>
> >> John
>
> >> > Yann
>
> --
> William Stein
> Associate Professor of Mathematics
> University of Washingtonhttp://wstein.org
--~--~---------~--~----~------------~-------~--~----~
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-devel
URLs: http://www.sagemath.org
-~----------~----~----~----~------~----~------~--~---

Reply via email to