valuesfrom

Valuesfrom is a term commonly used in discussions of value restrictions within ontologies, particularly in the context of the Web Ontology Language (OWL). It is not a standalone formal keyword in OWL; the standard constructs are someValuesFrom and allValuesFrom, which are used inside class expressions to constrain the values a property can take.

In OWL 2, someValuesFrom and allValuesFrom implement existential and universal value restrictions, respectively. SomeValuesFrom restricts a property so that an individual must have at least one value that belongs to a specified class. AllValuesFrom restricts a property so that all values of the property belong to the specified class. These restrictions are central to modeling domain concepts where relationships are constrained to particular kinds of related objects.

Examples (in commonly used syntaxes):

- Manchester syntax: Person subClassOf hasPet someValuesFrom Dog. This expresses that there exists at least one hasPet value that is a Dog.

- Manchester syntax: Person subClassOf hasPet allValuesFrom Dog. This expresses that every hasPet value is a Dog.

- Functional-style equivalents: ObjectSomeValuesFrom(:hasPet, :Dog) and ObjectAllValuesFrom(:hasPet, :Dog). Similar forms exist for data properties (DataSomeValuesFrom and DataAllValuesFrom).

Usage and implications:

These value restrictions support ontology design and reasoning tasks, enabling classifiers to infer class memberships and detect inconsistencies. They are widely used in knowledge graphs, biomedical ontologies, and semantic data models to encode domain rules without enumerating all individuals.

Notes:

The hyphenated term “valuesFrom” itself is not a formal OWL keyword; practitioners typically refer to someValuesFrom or allValuesFrom. In tooling, you may encounter a shorthand or UI label that uses "valuesFrom" to denote the concept of value restrictions.