Re: Mathematica "Reduce" function

[Pedro Fortuny Ayuso <fortunypedro@uniovi.es>]

On Thu, Mar 02, 2017 at 10:05:11AM +0100, Rafael Guglielmetti wrote:
> Dear all,
> I step (maybe too late) in the discussion with a small question: If
> k is big, would it be interesting to parallelize the first (i.e.
> external) loop?

Certainly, I actually would divide the computation first when k
is big, into several smaller parts.

Thanks,

Pedro.



> 
> Best,
> 
> Rafael
> 
> On 03/02/2017 10:00 AM, Pedro Fortuny Ayuso wrote:
> >Thanks to all.
> >
> >My specific problem is trying to solve equations like
> >
> >6x^2 + 12y^2 +20z^2 = 0
> >
> >over Z/(2^k)Z. That is, finding the points of that surface
> >over that ring.
> >
> >Bill's reply of counting
> >
> >length([[x,y,z]|x<-[0..2^k-1];y<-[0..2^k-1];z<-[0..2^k-1],6*x^2+12*y^2+20*z^2==0])
> >
> >is the fastest but it ***looks like*** a lot slower than
> >Mathematica (but please notice I am working on a system
> >with pari/gp and my colleague on a different one with Mathematica,
> >so that it may have nothing to do with pari/Mathematica).
> >
> >I know nothing about number theory, I just can guess what
> >'solving on the p-adics and then lifting' might mean but
> >am not quite ready to implement it.
> >
> >Thanks again,
> >
> >
> >Pedro.
> >
> >
> >
> 
> 

-- 
Pedro Fortuny Ayuso
http://pfortuny.net


EPIG, Campus de Viesques, Gijon
Dpto. de Matematicas
Universidad de Oviedo