> On Sep 6, 2007, at 3:41 AM, s z wrote:
>
> > Hi,
> >
> > I have encountered a problem that how to use OWL to model the
> > knowledge of calculation.
> > A simple example can be seen as the following:
> >
> > The knowledge about calculating tax is expressed as:
> > Tax = TotalAmount * taxRate
It's also somewhat straightforward to express this sort
of thing using rules. Using N3 rules, it would look like:
{ ?TRX subtotal ?X.
?TRX taxRate ?Y.
(?X ?Y) math:product ?TOTAL. }
=> { ?TRX tax ?TOTAL }.
For details on N3, see
http://www.w3.org/DesignIssues/Notation3N3 is a somewhat experimental design; the W3C
Rule Interchange Format is working on a standard
for rule interchange. They have released drafts
such as:
RIF Core Design
W3C Working Draft 30 March 2007
This version:
http://www.w3.org/TR/2007/WD-rif-core-20070330Latest version:
http://www.w3.org/TR/rif-coreI write about rules in a category of my blog...
http://dig.csail.mit.edu/breadcrumbs/taxonomy/term/30Hmm... public-owl-dev might be a better mailing list
than public-webont-comments, as we're not really
discussing details of the text of the spec.
On Thu, 2007-09-06 at 18:24 -0400, Alan Ruttenberg wrote:
> OWL can not calculate the results of such expressions.
>
> It can model the calculation, in the sense of supplying enough
> information to some interpreter to do that calculation. See for
> example:
http://neno.lanl.gov/Home.html> -Alan
> >
> > I could not figure out a way to do it in OWL.
> > Can OWL only express the logical relations among classes?
> > Please help? Many thanks!
> >
> > Su
--
Dan Connolly, W3C
http://www.w3.org/People/Connolly/