where can I find graph input resources/files?

Question

Hi!
I want to test various algorithms on graphs.
Does anyone know a web where I can get lots of examples in text files? I've found many examples but they are always images. I want a text description of a graph, by edge listing or whatever... do you know one such source?

Thanks!
Manuel

Answer 1

Graph problems are common in programming competitions.
I don't know if you are used to the format of those competitions, but here's a list of some of the online judges where you can submit/test your solution online:

• UVA (Probably the biggest ACM problems database, to help you, here's a list of some graph problems)
• Spoj
• SGU

Topcoder has also a great problem database (see problem archive) But it'll take you something to get used to it. (Note that it's not just the problems, you can also use the arena to test/submit your solutions)

Answer 2

RDF datasets are graphs, try rdfdata.org, dbpedia which is wikipedia in RDF, the LUBM graph benchmark, or a really big one (currently down at 2009-11-19 21:18 GMT).

Also wordnet is a graph.

Answer 3

Hi

Or go to the source, The Stanford Graphbase: http://www-cs-faculty.stanford.edu/~knuth/sgb.html

Regards

Mark