pyowl2.class_expression.object_union_of

An implementation of the OWL object union construct that represents the logical disjunction of multiple class expressions.

Description

OWLObjectUnionOf models the logical disjunction of multiple class expressions within an ontology, representing individuals that belong to at least one of the constituent classes. The implementation enforces a canonical internal representation by automatically sorting the provided list of expressions during initialization and modification, which ensures consistency for comparisons and hashing regardless of the input order. It requires a minimum of two class expressions to construct a valid union, preventing the creation of degenerate logical structures. Furthermore, the logic provides a string representation that adheres to standard functional syntax, outputting the union operator followed by the sorted components.

Classes

OWLObjectUnionOf

This class models a logical union (disjunction) of class expressions, defining a group of individuals that belong to at least one of the constituent classes. It is used to construct complex, inclusive definitions within an ontology by combining multiple class criteria. When initializing or modifying this object, a list of at least two OWLClassExpression instances must be provided; the list is automatically sorted to ensure a consistent internal representation.

Module Contents

UML Class Diagram for OWLObjectUnionOf

class OWLObjectUnionOf(expressions: list[pyowl2.abstracts.class_expression.OWLClassExpression])

Bases: pyowl2.abstracts.class_expression.OWLClassExpression

This class models a logical union (disjunction) of class expressions, defining a group of individuals that belong to at least one of the constituent classes. It is used to construct complex, inclusive definitions within an ontology by combining multiple class criteria. When initializing or modifying this object, a list of at least two OWLClassExpression instances must be provided; the list is automatically sorted to ensure a consistent internal representation.

Parameters:

classes_expressions (list[OWLClassExpression]) – Sorted list of class expressions comprising the union, containing at least two elements.

__str__() → str

Returns a human-readable string representation of the object union expression. The output is formatted by concatenating the literal “ObjectUnionOf(” with the string representations of the constituent class expressions, which are joined by single spaces, and terminating with a closing parenthesis. This method provides a standard functional syntax view of the logical structure without modifying the object’s state.

Returns:

A string representation of the object union, formatted as “ObjectUnionOf(…)” containing the string representations of the constituent class expressions.

Return type:

str

_classes_expressions: list[pyowl2.abstracts.class_expression.OWLClassExpression]

property classes_expressions: list[pyowl2.abstracts.class_expression.OWLClassExpression]

Assigns a new list of class expressions to serve as the operands for this union. The input list is sorted before being stored internally to maintain a consistent, canonical order, regardless of the order provided by the caller. This method replaces the existing collection of expressions rather than modifying it in place.

Parameters:

value (list[OWLClassExpression]) – A list of OWL class expressions to assign. The list will be sorted before storage.