#19123: LatticePoset: add is_vertically_decomposable
-------------------------------------+-------------------------------------
Reporter: jmantysalo | Owner:
Type: enhancement | Status: needs_work
Priority: major | Milestone: sage-7.0
Component: combinatorics | Resolution:
Keywords: | Merged in:
Authors: Jori Mäntysalo | Reviewers:
Report Upstream: N/A | Work issues:
Branch: | Commit:
u/jmantysalo/vertically_decomposable2|
b408d0c9dd34b9c07ca3472d7e12615dc7072457
Dependencies: | Stopgaps:
-------------------------------------+-------------------------------------
Changes (by jmantysalo):
* status: needs_review => needs_work
* milestone: sage-6.9 => sage-7.0
Comment:
Documentation part (i.e. index of functions) done in #19854, so this one
needs work.
Also this should be thinked about. There is also #19659 waiting, and in
principle it is same thing as this one; a poset that is also a lattice can
be expressed as an ordinal sum of two posets only if it vertically
decomposable. At least http://users.cecs.anu.edu.au/~bdm/papers/posets.pdf
by Brinkmann and McKay uses term "vertically decomposable" with non-
lattice posets.
(Actually after #19659 it is easy to make a simple function for #19215,
and then use it as a "precompiler" for #14126. But that's another story.)
--
Ticket URL: <http://trac.sagemath.org/ticket/19123#comment:47>
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 unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
To post to this group, send email to [email protected].
Visit this group at https://groups.google.com/group/sage-trac.
For more options, visit https://groups.google.com/d/optout.
