This is now:
https://github.com/sagemath/sage/pull/38459
On Wednesday 31 July 2024 at 08:46:14 UTC-7 Nils Bruin wrote:
> On Wednesday 31 July 2024 at 07:33:47 UTC-7 Georgi Guninski wrote:
>
> I need non-torsion element of Jacobian of hyperelliptic curve,
> would someone give example?
>
> IIRC something very close to the following worked about
> 5 years ago, but now I get trivial result.
>
> Session:
> #Author: Georgi Guninski
> K.<x>=QQ[]
> C=HyperellipticCurve(x^5+x+5^2-2);
> J=C.jacobian();
> P=J(1,5);
> 2*P
> #(1) ##is this correct?
>
>
> Yes, it is correct. To get a non-torsion element:
>
> D=J(x-1,5)
>
> For your other report:
>
> K.<u>=QQ[]
> C=HyperellipticCurve(u^5+u+5^2-2);
> J=C.jacobian();
> print("J=",J);
> P=J(1,5); #error here
>
> If you change the last line to P=J(1*u^0,5*u^0) then it does work. It
> looks like there is some preprocessing on the arguments that changes
> constants into polynomials and it looks like this has been hardcoded to
> J.base_ring()['x']. It should use
>
> J.curve().hyperelliptic_polynomials()[0].parent()
>
> instead.
>
>
--
You received this message because you are subscribed to the Google Groups
"sage-devel" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to sage-devel+unsubscr...@googlegroups.com.
To view this discussion on the web visit
https://groups.google.com/d/msgid/sage-devel/057e7637-9f4a-44f5-9f61-32cb769ffbd8n%40googlegroups.com.
