#19545: Mathon's pseudocylic strongly regular graphs.
-------------------------+-------------------------------------------------
Reporter: | Owner:
dimpase | Status: new
Type: | Milestone: sage-6.10
enhancement | Resolution:
Priority: major | Merged in:
Component: graph | Reviewers:
theory | Work issues:
Keywords: | Commit:
Authors: Dima | 4c7cb931a9b80cde29d55e31a1fb219f20a4899b
Pasechnik | Stopgaps:
Report Upstream: N/A |
Branch: |
u/dimpase/matpc |
Dependencies: |
-------------------------+-------------------------------------------------
Comment (by dimpase):
Replying to [comment:9 ncohen]:
> Hello Dima,
>
> I don't think that we need some specific function that would manage both
paley graphs and these ones, but that's probably up to you given that I
have not read the code yet. I usually prefer to keep things as simple as
possible, so one `is_` function by constructor is fine with me.
>
> About your `is_` function, I do not understand why you would need
something different from the usual output: it *does* tell you with
certainty that there is a way to build the function.
The situation with (4z+1,2z,z-1,z)-graphs is akin to these ones that come
from Hadamard matrices only in this case we have conference matrices, of
size 2 (mod 4), which is the number `v` of
graph vertices +1.
With Hadamard graphs, we have these RHCD (sp?) recursive constructions of
yours; for conference
matrices, we have yet to code such a recursive construction).
Apart from Paley and the construction of this ticket, there are
potentially more (e.g. some OAs
can give such graphs, when `v` is a square).
Where do we put such a construction?
--
Ticket URL: <http://trac.sagemath.org/ticket/19545#comment:10>
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 http://groups.google.com/group/sage-trac.
For more options, visit https://groups.google.com/d/optout.
