#8922: induced subgraph search
-------------------------------+--------------------------------------------
Reporter: ncohen | Owner: jason, ncohen, rlm
Type: enhancement | Status: needs_review
Priority: critical | Milestone: sage-4.4.4
Component: graph theory | Keywords:
Author: Nathann Cohen | Upstream: N/A
Reviewer: Minh Van Nguyen | Merged:
Work_issues: |
-------------------------------+--------------------------------------------
Changes (by mvngu):
* reviewer: => Minh Van Nguyen
Old description:
> This patch add to Sage the method Graph.induced_subgraph_search which
> looks for a given graph as an induced subgraph of "self".
>
> This is done through exhaustive search, using a very basic new graph
> class hand-made to efficiently stand such repetitive operations !
>
> I tried to document the code so that it could be somewhat easy to review,
> but feel free to ask any question about it ! :-)
>
> '''Apply:'''
>
> 1. #7529
> 1.
> [http://trac.sagemath.org/sage_trac/attachment/ticket/8922/trac_8922.patch
> trac_8922.patch]
New description:
This patch add to Sage the method Graph.induced_subgraph_search which
looks for a given graph as an induced subgraph of "self".
This is done through exhaustive search, using a very basic new graph class
hand-made to efficiently stand such repetitive operations !
I tried to document the code so that it could be somewhat easy to review,
but feel free to ask any question about it ! :-)
'''Apply:'''
1. #7529
1.
[http://trac.sagemath.org/sage_trac/attachment/ticket/8922/trac_8922.patch
trac_8922.patch]
1.
[http://trac.sagemath.org/sage_trac/attachment/ticket/8922/trac_8922-reviewer.patch
trac_8922-reviewer.patch]
--
Comment:
Changes in reviewer patch:
* Move the method `adjacency_sequence()` to the class `CGraph`, as I
think that method is useful for both dense and sparse graphs.
* Clean-up coding style in accordance with PEP 008.
* In describing the algorithm used in `subgraph_search()` of the module
`generic_graph_pyx.pyx`, you have the formula:
{{{
`\binom k!{|V(G)|}{k}`
}}}
That won't typeset in LaTeX as you expected. Do you mean this?
{{{
`k! \binom{|V(G)|}{k}`
}}}
I have used the latter formula in my reviewer patch. Please correct me if
I'm wrong.
* Unit tests for the `cdef` functions `vectors_equal()` and
`vectors_inferior()`, and the method `adjacency_sequence()`. These
functions/methods are defined using `cdef` and the doctest coverage script
don't pick them up in its analysis. However, I still think it's important
to provide unit tests for such functions/methods.
* Amalgamate the methods `induced_subgraph_search()` and
`subgraph_search()`. Their definitions are almost identical, except for
the keyword `induced`. The combined method is defined to take the boolean
keyword `induced` and pass it on to the relevant method.
Another pair of eyes is needed to look over my reviewer patch.
--
Ticket URL: <http://trac.sagemath.org/sage_trac/ticket/8922#comment:11>
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.
