buildingSMART Forums

Where can I find computer interpretable descriptions for IFC4Add2?

#1

I see that IFC4Add2 offers computer interpretable listings, but although it is great, it doesn’t include any human descriptions for types or classes. Does this exist? If not, I suggest it be added, as it can be automatically parsed to produce documentation in vendors.

#2

I do not understand the question. What you you mean with computer interpretable descriptions? Could you explain?

#3

Sorry, I meant human descriptions, for instance on the computer interpretable page for Psets, it includes human descriptions e.g. the string “Date on which the overall condition is assessed”:

http://www.buildingsmart-tech.org/ifc/IFC4/Add2/html/psd/Pset_Condition.xml

Whereas the other computer interpretable listings here do not include any human descriptions:

http://www.buildingsmart-tech.org/ifc/IFC4/Add2/html/annex/annex-a.htm

#4

yes, but what are you missing? The inclusion of the description of classes and properties as comments directly in the EXPRESS or XSD code?

We didn’t do it. But you can automatically fetch each description by:
…://www.buildingsmart-tech.org/ifc/“release”/“addendum”/htmml/link/“name of construct”.htm
e.g. http://www.buildingsmart-tech.org/ifc/IFC4/Add2/html/link/ifcactor.htm

#5

I am missing the human descriptions. E.G. each IFC class’ attribute tables have a “Description” column. For that IfcActor example, the description column for the TheActor attribute is "Information about the actor. " - this information is not present in the EXPRESS or XSD or any computer interpretable listing. Similarly, there are no descriptions present for any enum definitions, such as in http://www.buildingsmart-tech.org/ifc/IFC4/Add2/html/link/ifcactor.htm - the enums are there in the XSD but do not have any human description.

I’d like to extract the human descriptions so that it can be used as information in an implementation to guide the user to enter in the right information.

I know it is possible to scrape HTML for the descriptions, but that is akin to scraping the UI, which is not a proper solution. That is why computer interpretable listings exist in the first place.

Can it be added to the EXPRESS / XSD for IFC4 and all future IFC releases?

#6

If this isn’t resolved, I’d like to add this to the agenda for the ISG @jwouellette

It would be good if computers could extract human descriptions, so that they can be relayed on to users of the vendors.