Hi Irene, thanks for the suggestion. I tried to create a class "RealParameter" to represent the Quantity with property values and then created an instance called "SPR000-srate" in the ontology. Afterwards, I changed the srate property shape from attribute to relationship and set the default value to the "SPR000-srate".
In the data graph, I created a new instance "new_srate" of "RealParameter" and assigned different values to title, unit and value fields. By default, it takes the value "SPR000-srate", but I was able to swtich the value to "new_srate". I see several drawbacks, however: 1) In the ontology, I would end up with creating thousands of "RealParameter" instances. In my domain, I have to model several thousands such classes to represent a modeling library, and some classes have up to 20 parameters. 2) I can only override the value by switching the whole object. It is not possible to only override for example unit and take the value from the default title. I have to copy the title value from the default instance to the new instance even if it is not changed at all. This is how it looks like with this approach: [image: srate-default-par.png] I was thinking of modelling these classes as taxonomy after I saw your teaching video about taxonomy. However, my current business problem is creating instances of these classes and override values. If these classes/parameters would be all concepts, I would need to create some custom relationship (e.g. conformsTo) between them and their instances, since both are individuals from RDF ponit of view. The semantics would be very weak. How about your opinion? Best regards, Kai Irene Polikoff schrieb am Dienstag, 2. November 2021 um 01:01:49 UTC+1: > Yes, reification would let you cut the number of property shapes to just > 22: 20 for the different properties that will hold values of your > quantities/measurements plus the two for the title and the unit of measure. > > However, you would not be able to specify a default value as you would > only have a single property shape for the unit of measure property. > > Another option is to have a class Quantity with properties value, unit of > measure and title. Then, properties like srate become relationships and you > would be creating new instances for each quantity. I think you should then > be able to specify a default value for the srate/unit sequential path, but, > without trying this out, I am not sure how practical this would be I.e., > how well it would work in the EDG UI. > > > On Nov 1, 2021, at 7:34 PM, Kai Liu <[email protected]> wrote: > > In EDG, I have a class "Spring", on which a parameter "srate" of type > float should be defined. It has a default value. In addition, this > parameter should also carry some metadata, e.g. a default title "spring > rate", a default unit "N/m". The instances of this class can then override > these default values. > > > Currenlty, I defined for each of these metadata a separate attribute: > "srate.title" of type string, "srate.unit" of type string and specified > default values for them. I am wondering whether there is a modeling pattern > to better cope with this problem, since I have classes with 20 parameters, > and for which I need to define 60 attributes. Moreover, there are no > semantic relationship between srate, srate.title and srate.unit. They are > related just with the naming convention. > > I tried to use Reification (statements about statements) to model this, > but I was not able to set the default values for the title and unit in the > ontology. > > Thanks. > > Kai > > A screenshot of the property (attribute) definition: > > <srate.png> > > > The configuration of this parameter in the instance: > > <srate-instance.png> > > > > > -- > You received this message because you are subscribed to the Google Groups > "TopBraid Suite Users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/topbraid-users/972303f0-d963-41a9-9acc-5ef45193be59n%40googlegroups.com > > <https://groups.google.com/d/msgid/topbraid-users/972303f0-d963-41a9-9acc-5ef45193be59n%40googlegroups.com?utm_medium=email&utm_source=footer> > . > <srate.png> > <srate-instance.png> > > -- You received this message because you are subscribed to the Google Groups "TopBraid Suite Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/topbraid-users/2925ec83-395a-400e-b126-348646eb791an%40googlegroups.com.
