Supported OWL 2 Language Features

OWL Axioms

OWL Class Expressions

In OWL 2, classes and property expressions are used to construct class expressions, sometimes also called descriptions, and, in the description logic literature, complex concepts. Class expressions represent sets of individuals by formally specifying conditions on the individuals’ properties; individuals satisfying these conditions are said to be instances of the respective class expressions.

DL-Learner supports the generation of class expressions based by using the following language constructs:

DL Syntax OWL 2
conjunction owl:intersectionOf
disjunction owl:unionOf
negation ¬ owl:complementOf
existential restriction owl:someValuesFrom
universal restriction owl:allValuesFrom
value restriction {a} owl:hasValue
cardinality restriction ≥n, ≤n, =n owl:minCardinality, owl:maxCardinality, owl:cardinality

Supported datatypes:

Based on the OWL 2 datatype map the following datatypes for the representation of real numbers, decimal numbers, and integers are supported:

  • owl:real
  • owl:rational
  • xsd:decimal
  • xsd:integer
  • xsd:nonNegativeInteger
  • xsd:nonPositiveInteger
  • xsd:positiveInteger
  • xsd:negativeInteger
  • xsd:long
  • xsd:int
  • xsd:short
  • xsd:byte
  • xsd:unsignedLong
  • xsd:unsignedInt
  • xsd:unsignedShort
  • xsd:unsignedByte

Additionally, a preliminary support for date literals is planned.