Re: [sage-devel] Re: Help and Advice | Arithmetic of Jacobians in the Split/Real Model is Broken

To make discussion on this point easier, I have made a GitHub issue: https://github.com/sagemath/sage/issues/37626 For progress on this code, we have all doctests passing from the old implementation except: - we cannot define toric varieties over rings, so we can't have hyperelliptic curves

Re: [sage-devel] Re: Help and Advice | Arithmetic of Jacobians in the Split/Real Model is Broken

Back again with more class questions and general advice help While getting all the old sage code into this new project, I realised there are places where we really rely on the underlying curve classes. One example is that we need ``` def dimension(): return 1 ``` To avoid some crashes,

Re: [sage-devel] Re: Help and Advice | Arithmetic of Jacobians in the Split/Real Model is Broken

Thanks so much for the context Oh interesting. In this case I wonder whether we should work on and include a new class (maybe something as simple as a WeightedProjectiveSpace and a curve from this) mirroring the implementation for the plane curves. Alternatively I could go into the old plane

Re: [sage-devel] Re: Help and Advice | Arithmetic of Jacobians in the Split/Real Model is Broken

One thing that may deserve a cursory check is the overhead involved in inheriting from AlgebraicScheme_subscheme_toric class . Some parent structures are optimized for prolonged use *after* creation and may do a lot of caching/precomputation. There may be scenarios where one wants to construct

Re: [sage-devel] Re: Help and Advice | Arithmetic of Jacobians in the Split/Real Model is Broken

Thanks David, there's a bunch of nice things we could do for genus two in various cases which would be worth including. The inert case, where all degree zero divisors (except the identity element) have u with degree 2 would probably allow something particularly nice. As another update I have

Re: [sage-devel] Re: Help and Advice | Arithmetic of Jacobians in the Split/Real Model is Broken

There is also this old trac ticket about implementing fast arithmetic in genus 2 Jacobians, which never made it into Sage. I've CCed Mike Jabobson, who worked on it. David On Tue, Mar 12, 2024 at 12:10 PM Giacomo Pope wrote: > Thank you for

Re: [sage-devel] Re: Help and Advice | Arithmetic of Jacobians in the Split/Real Model is Broken

Thank you for linking this and I agree this is a great way to cross-compare the work we have been doing. I am not an expert in this area so I am not sure I should do a full review but I'm happy to look over it if this helps. As a small update on this work, I now have class

Re: [sage-devel] Re: Help and Advice | Arithmetic of Jacobians in the Split/Real Model is Broken

On Friday, March 8, 2024 at 7:37:04 PM UTC+9 Giacomo Pope wrote: As a small update, the repository now contains code to - perform arithmetic for - the imaginary model (ramified, one point at infinity) for all cases - the real model (split, two points at infinity) for all cases - the real

Re: [sage-devel] Re: Help and Advice | Arithmetic of Jacobians in the Split/Real Model is Broken

As a small update, the repository now contains code to - perform arithmetic for - the imaginary model (ramified, one point at infinity) for all cases - the real model (split, two points at infinity) for all cases - the real model (inert, zero points at infinity) for even genus Which

Re: [sage-devel] Re: Help and Advice | Arithmetic of Jacobians in the Split/Real Model is Broken

Thanks for mentioning the related discussion. We checked that in the new implementation in Giacomo's repository, this issue is solved. In the example that was given in the chat, we obtain the following output: ``` sage: R. = QQ[] sage: f = 144*x^6 - 240*x^5 + 148*x^4 + 16*x^3 - 16*x^2 - 4*x + 1

Re: [sage-devel] Re: Help and Advice | Arithmetic of Jacobians in the Split/Real Model is Broken

It's still here: https://github.com/sagemath/sage/issues/32024 -- 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

Re: [sage-devel] Re: Help and Advice | Arithmetic of Jacobians in the Split/Real Model is Broken

Just wanted to mention that I posted about something similar a few years ago here: https://groups.google.com/g/sage-support/c/j1Y9yuu-VuE/m/cA7N8iqCCAAJ. At the time a trac ticket was opened, but I'm not sure about the status especially post the github migration. On Wed, Mar 6, 2024 at 11:55 AM

[sage-devel] Re: Help and Advice | Arithmetic of Jacobians in the Split/Real Model is Broken

On Wednesday 6 March 2024 at 04:52:16 UTC-8 Giacomo Pope wrote: I think aside from maybe needing additional methods on the hyperelliptic curve, once the projective model is right and points on the curve are well defined for all cases. I do not have any intuition on whether the balanced model