How to get a list of all classes in a namespace.

[Babroo]

Hello,

I have to use the namespace to define my ontology. I used a namespace for defining several classes in one ontology and then use ".classes()" and other attributes to return result from this namespace. I can have access to each class individually but I could not get a list of all classes through namespace. Is there any solution?


>>> from owlready2 import *

>>> onto1 = get_ontology("http://test.org/onto1.owl")
>>> obo1 = onto1.get_namespace('http://test.org/')

>>> with obo1:
    class MyNewClass1(Thing): pass
    class MyNewClass11(Thing): pass
    class MyNewClass111(Thing): pass

 
>>> print(obo1.base_iri)
http://test.org/

>>> print(obo1.MyNewClass1)
test.org.MyNewClass1

>>> print(list(obo1.classes()))
Traceback (most recent call last):
  File "<pyshell#13>", line 1, in <module>
    print(list(obo1.classes()))
TypeError: 'NoneType' object is not callable

[Jiba]

Hello,

The namespace defines an easy way to access to entities, but it does not maintain a separate list of entities and RDF triples (as an ontology does). This is why namespaces do not have .classes() and the likes.

The only solution is to search entities by IRI and to filter classes, as follows:

>>> [i for i in default_world.search(iri = "http://test.org/*") if isinstance(i, ThingClass)]
[test.org.MyNewClass1, test.org.MyNewClass11, test.org.MyNewClass111]

Best regards,
Jiba