Re: Working modulo 2
- To: mathgroup at smc.vnet.net
- Subject: [mg92120] Re: Working modulo 2
- From: Peter Pein <petsie at dordos.net>
- Date: Sat, 20 Sep 2008 05:01:27 -0400 (EDT)
- References: <gavt0g$g4u$1@smc.vnet.net>
me13013 schrieb:
> Howdy,
>
> How does one reduce a polynomial's coefficients modulo 2? For
> example, I have a function that sums several polynomials, and
> currently produces a result like this:
> 7 + x + 4 y + 4 x y + 3 z + 2 x z + 4 y z + 4 x y z
> I want to reduce this to
> 1 + x + z
>
> I thought I might be able to do this by somehow coercing the terms
> into a list and then doing Sum[L[[i]],{i,1,Length[L]},Modulus->2], but
> no such luck.
>
> Any ideas?
>
> Thanks,
> Bob H
>
Hi Bob,
ReplaceAll is what you need:
7+x+4 y+4 x y+3 z+2 x z+4 y z+4 x y /.i_Integer:>Mod[i,2]
1+x+z
Peter