#9713: Add toric Chow group
----------------------------------+-----------------------------------------
Reporter: vbraun | Owner: AlexGhitza
Type: enhancement | Status: needs_work
Priority: major | Milestone: sage-4.6
Component: algebraic geometry | Keywords:
Author: Volker Braun | Upstream: N/A
Reviewer: Andrey Novoseltsev | Merged:
Work_issues: |
----------------------------------+-----------------------------------------
Changes (by novoselt):
* status: needs_review => needs_work
Comment:
Some preliminary comments:
1. The new module is not completely documented yet, `sage -coverage`
shows some issues.
1. It seems to me that it is more common to use A^k^ rather than
A,,d-k,,, so I think it would be better to stick with it in the
documentation.
1. I'd prefer to drop "The " from "The Chow cycle ..." in `_repr_` as was
done for divisor classes.
1. It is not clear how to construct Chow cycles (except for those that
correspond to cones).
1. It is not clear what do numbers mean in the representation - i.e. how
the basis is chosen?
1. Regardless of the chosen basis, I think it would be more useful to see
cycles as linear combination of cones (perhaps with cones represented by
their `ambient_ray_indices`), without seeing those that got zero
coefficients, of course. This issue is also relevant for
divisor/cohomology classes and for divisor classes we do use coordinates
in some basis, but I think that it makes more sense there, while here
basis elements can be given by cycles of different dimension and having no
separation between them makes it difficult to interpret the output.
--
Ticket URL: <http://trac.sagemath.org/sage_trac/ticket/9713#comment:3>
Sage <http://www.sagemath.org>
Sage: Creating a Viable Open Source Alternative to Magma, Maple, Mathematica,
and MATLAB
--
You received this message because you are subscribed to the Google Groups
"sage-trac" group.
To post to this group, send email to [email protected].
To unsubscribe from this group, send email to
[email protected].
For more options, visit this group at
http://groups.google.com/group/sage-trac?hl=en.
