An ontology diagram shows classes, object properties and datatype properties, as well as rules (especially set rules). 

Symbols (Classes, Set Rules, Datatypes and Instances) are dragged from the palette into the drawing canvas. 

Connections (subClassOf, SetRelation, ObjectProperty, DatatypeProperty and Instantiation) connect the appropriate symbols.

The ontology diagram symbols palette provides the set of symbols and links which are used to graphically represent the ontology:

  • Class (symbol for a Class which may be automatically colored based on the Class characteristics)
  • Union, Intersection, Disjioint and Complement (symbols for set Rules)
  • owlDataType (symbol for defining the data type of a data Property defining a Class)
  • Instance (symbol for instances of a given Class)
  • subClassOf (connector linking a Class as subClass to its superClass Class)
  • SetRelation (connector linking a Class or a set Rule to a set Rule; composite rules can be formalized)
  • ObjectProperty (connector linking a Class or Set Rule to a Class or a set Rule defining the entertained relationship)
  • DatatypeProperty (connector linking a Class oa setRule to a Datatype)

owlInstanciation (connector linking a Class or a setRule to corresponding Instances)

As in any QualiWare diagram, connecting 2 symbols is achieved by selecting the connector, then the source symbol, then the target symbol, then giving it a name.

The coloring of the Class symbol is achieved based on the Class characteristics.

A class can be:

  • A Thing
  • A standard owl Class defined in the current ontology edited in the currentontology diagram
  • External to the concerned ontology (the one edited in the diagram)
  • A rdfs Class
  • A Resource
  • A deprecated Class

Since it is contextual to the edited diagram, defining a Class as being external to an ontology is achieved by selecting the classes which are external to the ontology depicted in the diagram copying them and pasting them in the “External Classes” field of the definition template of the diagram.


The same can be achieved for ObjectProperties which are external to the edited ontology.


A same Class (unique in the repository) can be a standard owl Class in the ontology defining it (and appearing pale blue in the diagram depicting this ontology) and dark blue (since external) in possibly many other diagrams depicting other ontologies referencing to this Class.

Same for ObjectProperties.


When closing a diagram, the corresponding Ontology instance (the one which refers to the diagram) is updated. Its contained Classes and Object Properties fields are updated.

The instances of Class, ObjectProperty, DatatypeProperty and set Rules instances edited in the diagram are also updated (see corresponding paragraphs)

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