Re: Question on elliptic curve group orders...

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

On Sun, Jan 22, 2017 at 02:03:29PM -0600, wraithx@morpheus.net wrote:
> Hello all,
> 
> I have some code that should work in Sage, but I don't have that installed.
> I do have pari/gp installed.  Can someone help me convert the following code
> so that I can run it in pari/gp?

FindGroupOrder(p,s)=
{
    K = Mod(1,p);
    v = K*(4*s);
    u = K*(s^2-5);
    x = u^3;
    b = 4*x*v;
    a = (v-u)^3*(3*u+v);
    A = a/b-2;
    x = x/v^3;
    b = x^3 + A*x^2 + x;
    E = ellinit([0,b*A,0,b^2,0],K);
    factor(ellcard(E))
}

the others are similar except for
x,y = P.xy()
which is
[x,y] = P;

Cheers,
Bill.