[rdfweb-dev] Re: Parsing FOAF in perl?

Jim Ley jim at j...
Thu Dec 12 20:28:31 UTC 2002

"Danny Ayers" <danny666 at v...>

>>Hmm i can't find the software, hope its still up there somewhere. I'd
>>love to have an excuse to revisit this stuff (mutters about lapsed
>>phd) but I expect realistically I won't.

>> FOAF-harvested data should be an interesting
>>thing to feed to such algorithms though, although the data isn't
>>that rich. If there were more Wordnet and Dmoz classifications being
>>for eg., I'd expect some interesting testbeds...

Okay, I've had a shot at adding a SOM to foafnaut, I found an algorithm
(this was before this recent discussion) in
http://members.ozemail.com.au/~dekker/snavis.pdf and have tried to
implement it, but it doesn't seem to work brilliantly, there's probably a
bug somewhere in my implementation The main problem is people all an
equal distance from a person normally seem to all end up on top of each
other * but I think the methodology is certainly feasible, and the
performance is surprisingly good.

http://jibbering.com/2002/12/foafnaut.png is an example of what you get,
the clustered people are all clustered on their nodes. Unfortunately it
often seems to crash my Adobe SVG with a "Pure virtual function call
error" which doesn't stop the script continuing, but you can't use the
browser after you dimiss the error.

Implementing this means I've had to implement Damians path finding
algorithm, which is very useful, although how paths might be exposed in
the foafnaut interface is an "opportunity", especially with the stability
problems making it difficult to have large datasets.

if you want to try it out yourself,
http://jibbering.com/foaf/foafnaut.som.svg open up a load of people, then
click on the key button (we've still not got a key, so for now I've taken
it over.)

Any feedback useful.



* which unfortunately doesn't happen to the people I know in the real
world - other than the Rugby players at any rate

More information about the foaf-dev mailing list