Hello Rob, We are in a group and we discussed it.
We have three data properties , CryptographyScore, SoftwareEngineering score and NetworkingScore and we need the maximum of these three scores for a student. Can we do it like this SELECT ?student (MAX(?score1, ?score2, ?score3) AS ?topScore) On Wed, Jan 4, 2017 at 5:05 PM, Rob Vesse <rve...@dotnetrdf.org> wrote: > Most likely not > > You seem to be running into the XY problem a lot (http://xyproblem.info) > > You keep asking how to do things with rules for which rules are not really > designed. And from some of your responses it sounds like the problems > you’re trying to solve don’t actually need rules at all. > > For example finding the top score for a student would be much more easily > done with a SPARQL query although from what little I have seen of your data > model it looks like it would make it even that quite awkward. But in > general terms something like the following would work: > > PREFIX ex: <http://example.com/ns/> > SELECT ?student (MAX(?score) AS ?topScore) > WHERE > { > ?student ex:score ?score . > } > GROUP BY ?student > > Rob > > On 04/01/2017 13:25, "javed khan" <javedbtk...@gmail.com> wrote: > > Thanks Dave and Lorenz for your response. > > What if we have entered the score for a student in Cryptography and > SoftwareEngineering and did not entered for Networking subject and > stored > something like this in our owl file: > > Student1 > > Name: Bob > CryptographyScore: 60 > SoftwareEngineeringScore: 80 > //NetworkingScore, not mentioned here > > Then will the above rule fires? > > > > On Wed, Jan 4, 2017 at 11:35 AM, Lorenz B. < > buehm...@informatik.uni-leipzig.de> wrote: > > > Inline comments: > > > I have three subjects marks for a student. > > > Cryptography, Networking, Software Engineering with different > marks for > > > each student. > > > I want to calculate in which subject a student got maximum marks > using > > Jena > > > rule and will set that subject as HighScoreSubject of the student ( > > > HighScoreSubject is data propety) whose values will be one of > these three > > > subjects. > > > > > > Is this rule correct to get the required result ( I am asking this > > because > > > I am not getting the result required) > > Without seeing the data, it's always difficult to say if something is > > correct or not. Sample data makes things easier. > > And without knowing how you apply the rules (in a correct syntax) > it's > > even harder. That means, it's always good to show the relevant code. > > > > > > ?x rdf:type std:Student + ?x std:CryptographyScore ?score1 + ?x > > > std:NetworkingScore ?score2 + ?x std:SEScore ?score3 + > > > greaterThan(?score1,?score2), greaterThan(?score1, ?score3) --> > > > ?x std:HighScoreSubject std:Cryptography > > > > > This rule covers only the case when the score for Cryptography is the > > highest. If your data doesn't contain a student that matches the > rule, > > nothing will happen. > > > > > > Cheers, > > Lorenz > > > > -- > > Lorenz Bühmann > > AKSW group, University of Leipzig > > Group: http://aksw.org - semantic web research center > > > > > > > > > > > >
