#10167: three new methods in Poset
--------------------------------------------------+-------------------------
Reporter: chapoton | Owner:
sage-combinat
Type: enhancement | Status: closed
Priority: minor | Milestone:
sage-duplicate/invalid/wontfix
Component: combinatorics | Resolution: duplicate
Keywords: poset | Work_issues:
Upstream: N/A | Reviewer:
Author: Frédéric Chapoton, Nicolas Thiéry | Merged:
Dependencies: |
--------------------------------------------------+-------------------------
Changes (by nthiery):
* status: needs_review => closed
* resolution: => duplicate
* milestone: => sage-duplicate/invalid/wontfix
Old description:
> 1) I need the distributive lattice of order ideals of a poset:
>
> {{{
> sage: Posets.PentagonPoset().order_ideals_lattice()
> }}}
>
> 2) I need the poset of join irreducibles of a lattice:
>
> {{{
> sage: Posets.PentagonPoset().join_irreducibles_poset()
> }}}
>
> 3) The Coxeter tranformation of a poset is a matrix, defined using the
> order matrix and its inverse, which is useful in the study of the derived
> category attached to the poset.
>
> {{{
> sage: Posets.PentagonPoset().coxeter_transformation()
> }}}
>
> My procedure for the distributive lattice now works. N. Thiery has
> provided a procedure for the poset of join irreducibles. I have written a
> working procedure for the Coxeter transformation. They are all included
> in the patch below.
New description:
1) I need the distributive lattice of order ideals of a poset:
{{{
sage: Posets.PentagonPoset().order_ideals_lattice()
}}}
2) I need the poset of join irreducibles of a lattice:
{{{
sage: Posets.PentagonPoset().join_irreducibles_poset()
}}}
3) The Coxeter tranformation of a poset is a matrix, defined using the
order matrix and its inverse, which is useful in the study of the derived
category attached to the poset.
{{{
sage: Posets.PentagonPoset().coxeter_transformation()
}}}
My procedure for the distributive lattice now works. N. Thiery has
provided a procedure for the poset of join irreducibles. I have written a
working procedure for the Coxeter transformation. They are all included in
the patch below.
Notes: those changes are now included in #10998; this ticket can be closed
as soon as #10998 will go in.
--
--
Ticket URL: <http://trac.sagemath.org/sage_trac/ticket/10167#comment:6>
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.
