Thursday, June 30, 2005

Well the test didn't work, but I had to go to bed. When I got up in the morning yesterday, I spent 15 minutes looking at the problem, and discovered it wasn't really a problem. The code was working just fine, but I had a typo in the RDF for the axioms. Doh! :-)

It's really impressive how many entailments come out of the axioms alone. There are 33 axioms and this was increases to 120 statements after the entailments. When I ran the RDFS rules over the RDFS model (and it's OWL description) then it turned 643 RDF statements into over 1259 statements.

It was while I was looking at this that I discovered how useful entailments are, even simple ones like this. For a start, all of the types suddenly become available, even those that are not immediately evident. This in turn showed up a couple of simple errors I had in the RDF which had slipped past me before. It turns out that entailments from bad data can lead to a lot of statements that are very obviously wrong. Quite handy.

I didn't get to work much more on this, as I needed to get back to the NGC preparation.

XA Store
Yesterday I was lucky to have DavidM online while writing Javadoc for the transaction layer. This helped me to learn a lot about the newer parts of the code much faster than if I'd had to do it on my own. This will definitely help with the handover.

Today I spent several hours working out a timetable for the handover. I expected to do this in a couple of days, but DavidW needed something from me quickly. So I tried to write an email with a broad outline. However, I ended up writing a lot more than I thought I would, and I think I'm halfway to the full preparation. :-)

One more thing I'd like to do is to write up some diagrams of the file formats. This is all available by reading the source files, but they have to be carefully interpreted to work it out. Having diagrams on hand should be very useful.

Well I'm exhausted tonight, so I'll leave it here and get to more Javadoc in the morning.

No comments: