Re: T_FFELT to T_VEC

[Bill Allombert <Bill.Allombert@math.u-bordeaux1.fr>]

On Wed, Dec 07, 2011 at 08:52:30PM +0400, ÐÐÐÐÐÐÐ ÐÐÑÑ wrote:
> Hello, all!
> 
> I have a problem:
> 1. I have an GF(2^r) element A, where GF(2^r) is extended finite field.
> 2. I want to get the coefficients of A when it is decomposing over GF(2^r)
> standard basis.
> For example, for element a^5, where a is a primitive element of GF(4) ~
> GF(2)[x]/<x^2 + x + 1>
> I want to get a vector of coefficients: {1, 1}.
> 3. How can I do this? Problem is that A is a scalar

You can use Vecrev(A.pol)

? a=ffgen((x^2+x+1)*Mod(1,2),'a);
? A=a^5;
? Vecrev(A.pol)
%16 = [1, 1]

Cheers,
Bill.