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graphs: Strongly regular graph database #1307

Open jasongrout opened 16 years ago

jasongrout commented 16 years ago

From Chris Godsil's wishlist:

> 
>>> A database of small graphs. Put Ted Spence's strongly regular graphs
>>> into a
>>> database. (In this case the important thing is to have the graphs
>>> themselves,
>>> we would not necessarily need much data.)

CC: @sagetrac-mvngu @dimpase

Component: graph theory

Issue created by migration from https://trac.sagemath.org/ticket/1307

7c09a680-e216-4024-bb8e-9bfd4aa7f313 commented 15 years ago
comment:3

CC'ing myself

6bdad4c1-1e26-4f2f-a442-a01a2292c181 commented 15 years ago
comment:4

If it just consists in converting the 32,548 graphs with parameters (36-15-6-6) to some database, I could do that with a bit of scripting... I saw there was in SAGE_DATA a file graphs.db ( sqlite format ), and the trouble is that I do not know what it contains, how to open it, and how to build one myself if it is what you expect... Could I know a bit more about this ? :-)

jasongrout commented 15 years ago
comment:5

I believe that database just contains the data that is exposed here:

http://good.math.iastate.edu/grout/graphs/

You can download one of the many SQLITE GUI tools listed at http://www.sqlite.org/cvstrac/wiki?p=ManagementTools and look at the database.

6bdad4c1-1e26-4f2f-a442-a01a2292c181 commented 15 years ago
comment:6

Thank you !!! I understand how it works now :-)

Well, so what about this database ? Do you think it would be a good idea to build a sqlite database for Sage with these graphs ? I do not know, for example, if this database will be compressed in any way, because there are a lot of graphs available and it could become a bit heavy.. Is there anything more efficient, in case the users needs to enumerate them all ?

jasongrout commented 13 years ago
comment:7

Here is a worksheet showing how to convert the graphs on Ted's page to Sage graphs: http://test.sagenb.org/home/pub/17/

kcrisman commented 10 years ago
comment:8

Hey, this would be really useful. Jason, if you see this, can you paste that code here? Also, I'm not sure where your database lives now. This could easily become an optional database, and Magma also has such things.

6bdad4c1-1e26-4f2f-a442-a01a2292c181 commented 10 years ago
comment:9

(just a note: we have 4 constructors of families of strongly regular graphs from http://www.win.tue.nl/~aeb/graphs/srg/srgtab.html. AffineOrthogonalPolarGraph, OrthogonalPolarGraph, PaleyGraph, SymplecticGraph)

kcrisman commented 10 years ago
comment:10

Yes, just that's not a database :)