Quick Reference Guide
From OWL
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==Built-in Datatypes and Facets== | ==Built-in Datatypes and Facets== | ||
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| colspan="2"|[http://www.w3.org/TR/xmlschema11-2/#unsignedShort xsd:unsignedShort] ||colspan="2"|[http://www.w3.org/TR/xmlschema11-2/#unsignedByte xsd:unsignedByte] | | colspan="2"|[http://www.w3.org/TR/xmlschema11-2/#unsignedShort xsd:unsignedShort] ||colspan="2"|[http://www.w3.org/TR/xmlschema11-2/#unsignedByte xsd:unsignedByte] | ||
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| - | |rowspan="3"|[http://www.w3.org/2007/OWL/wiki/Syntax#Strings Strings] ||colspan="4"|[ | + | |rowspan="3"|[http://www.w3.org/2007/OWL/wiki/Syntax#Strings Strings] ||colspan="4"|[[PlainLiteral|rdf:PlainLiteral]] (RDF plain literals) |
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| [http://www.w3.org/TR/xmlschema11-2/#string xsd:string] ||[http://www.w3.org/TR/xmlschema11-2/#NCName xsd:NCName] ||[http://www.w3.org/TR/xmlschema11-2/#Name xsd:Name] ||[http://www.w3.org/TR/xmlschema11-2/#NMTOKEN xsd:NMTOKEN] | | [http://www.w3.org/TR/xmlschema11-2/#string xsd:string] ||[http://www.w3.org/TR/xmlschema11-2/#NCName xsd:NCName] ||[http://www.w3.org/TR/xmlschema11-2/#Name xsd:Name] ||[http://www.w3.org/TR/xmlschema11-2/#NMTOKEN xsd:NMTOKEN] | ||
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Revision as of 18:17, 31 May 2009
- Document title:
- OWL 2 Web Ontology Language
Quick Reference Guide (Second Edition)
- Authors
- Jie Bao, Rensselaer Polytechnic Institute
- Elisa F. Kendall, Sandpiper Software, Inc.
- Deborah L. McGuinness, Rensselaer Polytechnic Institute
- Peter F. Patel-Schneider, Bell Labs Research, Alcatel-Lucent
- Contributors
- Li Ding, Rensselaer Polytechnic Institute
- Ankesh Khandelwal, Rensselaer Polytechnic Institute
- Abstract
- The OWL 2 Web Ontology Language, informally OWL 2, is an ontology language for the Semantic Web with formally defined meaning. OWL 2 ontologies provide classes, properties, individuals, and data values and are stored as Semantic Web documents. OWL 2 ontologies can be used along with information written in RDF, and OWL 2 ontologies themselves are primarily exchanged as RDF documents. The OWL 2 Document Overview describes the overall state of OWL 2, and should be read before other OWL 2 documents.
- This document provides a non-normative quick reference guide to the OWL 2 language. It also provides links to other documents, including the OWL 2 Primer for language introduction and examples, the OWL 2 Structural Specification and Functional Syntax document for more details of the functional syntax, and the OWL 2 New Features and Rationale document for new feature descriptions.
- This is an editors' draft. The intended final status of this document has not yet been determined; since it may become a Recommendation, it should be considered a Recommendation-Track document for now.
The OWL Working Group solicits feedback on how to improve and update this document.
- Copyright © 2008-2009 W3C® (MIT, ERCIM, Keio), All Rights Reserved. W3C liability, trademark and document use rules apply.
Contents
Editor's Note: To do list:1 Names, Prefixes, and Notation
Names in OWL 2 are IRIs, often written in a shorthand prefix:local_name, where prefix: is a prefix name that expands to an IRI, and local_name is the remainder of the name. The standard prefix names in OWL 2 are:
Prefix Name Expansion rdf: http://www.w3.org/1999/02/22-rdf-syntax-ns# rdfs: http://www.w3.org/2000/01/rdf-schema# owl: http://www.w3.org/2002/07/owl# xsd: http://www.w3.org/2001/XMLSchema# We use notation conventions in the following table*:
Letters Meaning Letters Meaning Letters Meaning Letters Meaning C class expression CN class name D data range DN datatype name P object property expression PN object property name R data property A annotation property a individual aN individual name _:a anonymous individual (a blank node label) v literal n non-negative integer** f facet ON ontology name U IRI s IRI or anonymous individual t IRI, anonymous individual, or literal p prefix name _:x blank node (a1 … an) RDF list * All of the above can have subscripts. ** as a shorthand for "n"^^xsd:nonNegativeInteger
2 OWL 2 constructs and axioms
For an OWL 2 DL ontology, there are some global restrictions on axioms.
In the following tables the first column provides links to the Primer (if applicable) and the 2nd column provides links to the Functional Syntax.
2.1 Class Expressions
Language Feature Functional Syntax RDF Syntax named class CN CN universal class owl:Thing owl:Thing empty class owl:Nothing owl:Nothing Boolean Connectives and Enumeration of Individuals
Language Feature Functional Syntax RDF Syntax intersection ObjectIntersectionOf(C1 … Cn) _:x rdf:type owl:Class.
_:x owl:intersectionOf ( C1 … Cn ).union ObjectUnionOf(C1 … Cn) _:x rdf:type owl:Class.
_:x owl:unionOf ( C1 … Cn ).complement ObjectComplementOf(C) _:x rdf:type owl:Class.
_:x owl:complementOf C.enumeration ObjectOneOf(a1 … an) _:x rdf:type owl:Class.
_:x owl:oneOf ( a1 … an ).Object Property Restrictions
Language Feature Functional Syntax RDF Syntax universal ObjectAllValuesFrom(P C) _:x rdf:type owl:Restriction.
_:x owl:onProperty P.
_:x owl:allValuesFrom Cexistential ObjectSomeValuesFrom(P C) _:x rdf:type owl:Restriction.
_:x owl:onProperty P.
_:x owl:someValuesFrom Cindividual value ObjectHasValue(P a) _:x rdf:type owl:Restriction.
_:x owl:onProperty P.
_:x owl:hasValue a.local reflexivity ObjectHasSelf(P) _:x rdf:type owl:Restriction.
_:x owl:onProperty P.
_:x owl:hasSelf "true"^^xsd:boolean.exact cardinality ObjectExactCardinality(n P) _:x rdf:type owl:Restriction.
_:x owl:onProperty P.
_:x owl:cardinality n.qualified exact cardinality ObjectExactCardinality(n P C) _:x rdf:type owl:Restriction.
_:x owl:onProperty P.
_:x owl:qualifiedCardinality n.
_:x owl:onClass C.maximum cardinality ObjectMaxCardinality(n P) _:x rdf:type owl:Restriction.
_:x owl:onProperty P.
_:x owl:minCardinality n.qualified maximum cardinality ObjectMaxCardinality(n P C) _:x rdf:type owl:Restriction.
_:x owl:onProperty P.
_:x owl:minQualifiedCardinality n.
_:x owl:onClass C.minimum cardinality ObjectMinCardinality(n P) _:x rdf:type owl:Restriction.
_:x owl:onProperty P.
_:x owl:maxCardinality n.qualified minimum cardinality ObjectMinCardinality(n P C) _:x rdf:type owl:Restriction.
_:x owl:onProperty P.
_:x owl:maxQualifiedCardinality n.
_:x owl:onClass C.Data Property Restrictions
Language Feature Functional Syntax RDF Syntax universal DataAllValuesFrom(R D) _:x rdf:type owl:Restriction.
_:x owl:onProperty R.
_:x owl:allValuesFrom D.existential DataSomeValuesFrom(R D) _:x rdf:type owl:Restriction.
_:x owl:onProperty R.
_:x owl:someValuesFrom D.literal value DataHasValue(R v) _:x rdf:type owl:Restriction.
_:x owl:onProperty R.
_:x owl:hasValue v.exact cardinality DataExactCardinality(n R) _:x rdf:type owl:Restriction.
_:x owl:onProperty R.
_:x owl:cardinality n.qualified exact cardinality DataExactCardinality(n R D) _:x rdf:type owl:Restriction.
_:x owl:onProperty R.
_:x owl:qualifiedCardinality n.
_:x owl:onDataRange D.maximum cardinality DataMaxCardinality(n R) _:x rdf:type owl:Restriction.
_:x owl:onProperty R.
_:x owl:maxCardinality n.qualified maximum cardinality DataMaxCardinality(n R D) _:x rdf:type owl:Restriction.
_:x owl:onProperty R.
_:x owl:maxQualifiedCardinality n.
_:x owl:onDataRange D.minimum cardinality DataMinCardinality(n R) _:x rdf:type owl:Restriction.
_:x owl:onProperty R.
_:x owl:minCardinality n.qualified minimum cardinality DataMinCardinality(n R D) _:x rdf:type owl:Restriction.
_:x owl:onProperty R.
_:x owl:minQualifiedCardinality n.
_:x owl:onDataRange D.Restrictions Using n-ary Data Range
In the following table 'Dn' is an n-ary data range.
Language Feature Functional Syntax RDF Syntax n-ary universal DataAllValuesFrom(R1 … Rn Dn) _:x rdf:type owl:Restriction.
_:x owl:onProperties ( R1 … Rn ).
_:x owl:allValuesFrom Dn.n-ary existential DataSomeValuesFrom(R1 … Rn Dn) _:x rdf:type owl:Restriction.
_:x owl:onProperties ( R1 … Rn).
_:x owl:someValuesFrom Dn.2.2 Properties
Language Feature Functional Syntax RDF Syntax named object property PN PN universal object property owl:topObjectProperty owl:topObjectProperty empty object property owl:bottomObjectProperty owl:bottomObjectProperty inverse property ObjectInverseOf(PN) _:x owl:inverseOf PN Language Feature Functional Syntax RDF Syntax named data property R R universal data property owl:topDataProperty owl:topDataProperty empty data property owl:bottomDataProperty owl:bottomDataProperty 2.3 Individuals & Literals
Language Feature Functional Syntax RDF Syntax named individual aN aN anonymous individual _:a _:a literal (datatype value) "abc"^^DN "abc"^^DN 2.4 Data Ranges
Data Range Expressions
Language Feature Functional Syntax RDF Syntax named datatype DN DN data range complement DataComplementOf(D) _:x rdf:type rdfs:Datatype.
_:x owl:datatypeComplementOf D.data range intersection DataIntersectionOf(D1…Dn) _:x rdf:type rdfs:Datatype.
_:x owl:intersectionOf (D1…Dn).data range union DataUnionOf(D1…Dn) _:x rdf:type rdfs:Datatype.
_:x owl:unionOf (D1…Dn).literal enumeration DataOneOf(v1 … vn) _:x rdf:type rdfs:Datatype.
_:x owl:oneOf ( v1 … vn ).datatype restriction DatatypeRestriction(DN f1 v1 … fn vn) _:x rdf:type rdfs:Datatype.
_:x owl:onDatatype DN.
_:x owl:withRestrictions (_:x1 ... _:xn).
_:xj fj vj. j=1…n2.5 Axioms
Class Expression Axioms
Language Feature Functional Syntax RDF Syntax subclass SubClassOf(C1 C2) C1 rdfs:subClassOf C2. equivalent classes EquivalentClasses(C1 … Cn) Cj owl:equivalentClass Cj+1. j=1…n-1 disjoint classes DisjointClasses(C1 C2) C1 owl:disjointWith C2. pairwise disjoint classes DisjointClasses(C1 … Cn) _:x rdf:type owl:AllDisjointClasses.
_:x owl:members ( C1 … Cn ).disjoint union DisjointUnionOf(CN C1 … Cn) CN owl:disjointUnionOf ( C1 … Cn ). Object Property Axioms
Language Feature Functional Syntax RDF Syntax subproperty SubObjectPropertyOf(P1 P2) P1 rdfs:subPropertyOf P2. property chain inclusion SubObjectPropertyOf(ObjectPropertyChain(P1 … Pn) P) P owl:propertyChainAxiom (P1 … Pn). property domain ObjectPropertyDomain(P C) P rdfs:domain C. property range ObjectPropertyRange(P C) P rdfs:range C. equivalent properties EquivalentObjectProperties(P1 … Pn) Pj owl:equivalentProperty Pj+1. j=1…n-1 disjoint properties DisjointObjectProperties(P1 P2) P1 owl:propertyDisjointWith P2. pairwise disjoint properties DisjointObjectProperties(P1 … Pn) _:x rdf:type owl:AllDisjointProperties.
_:x owl:members ( P1 … Pn ).inverse properties InverseObjectProperties(P1 P2) P1 owl:inverseOf P2. functional property FunctionalObjectProperty(P) P rdf:type owl:FunctionalProperty. inverse functional property InverseFunctionalObjectProperty(P) P rdf:type owl:InverseFunctionalProperty. reflexive property ReflexiveObjectProperty(P) P rdf:type owl:ReflexiveProperty. irreflexive property IrreflexiveObjectProperty(P) P rdf:type owl:IrreflexiveProperty. symmetric property SymmetricObjectProperty(P) P rdf:type owl:SymmetricProperty. asymmetric property AsymmetricObjectProperty(P) P rdf:type owl:AsymmetricProperty. transitive property TransitiveObjectProperty(P) P rdf:type owl:TransitiveProperty. Data Property Axioms
Language Feature Functional Syntax RDF Syntax subproperty SubDataPropertyOf(R1 R2) R1 rdfs:subPropertyOf R2. property domain DataPropertyDomain(R C) R rdfs:domain C. property range DataPropertyRange(R D) R rdfs:range D. equivalent properties EquivalentDataProperties(R1 … Rn) Rj owl:equivalentProperty Rj+1. j=1…n-1 disjoint properties DisjointDataProperties(R1 R2) R1 owl:propertyDisjointWith R2. pairwise disjoint properties DisjointDataProperties(R1 … Rn) _:x rdf:type owl:AllDisjointProperties.
_:x owl:members ( R1 … Rn ).functional property FunctionalDataProperty(R) R rdf:type owl:FunctionalProperty. Datatype Definitions
Language Feature Functional Syntax RDF Syntax datatype definition DatatypeDefinition(DN D) DN owl:equivalentClass D. Assertions
Language Feature Functional Syntax RDF Syntax individual equality SameIndividual(a1 … an) aj owl:sameAs aj+1. j=1…n-1 individual inequality DifferentIndividuals(a1 a2) a1 owl:differentFrom a2. pairwise individual inequality DifferentIndividuals(a1 … an) _:x rdf:type owl:AllDifferent.
_:x owl:members (a1 … an).class assertion ClassAssertion(C a) a rdf:type C. positive object property assertion ObjectPropertyAssertion( PN a1 a2 ) a1 PN a2. positive data property assertion DataPropertyAssertion( R a v ) a R v. negative object property assertion NegativeObjectPropertyAssertion(P a1 a2 ) _:x rdf:type owl:NegativePropertyAssertion.
_:x owl:sourceIndividual a1.
_:x owl:assertionProperty P.
_:x owl:targetIndividual a2.negative data property assertion NegativeDataPropertyAssertion(R a v ) _:x rdf:type owl:NegativePropertyAssertion.
_:x owl:sourceIndividual a.
_:x owl:assertionProperty R.
_:x owl:targetValue v.Keys
Language Feature Functional Syntax RDF Syntax Key HasKey(C (P1 … Pm) (R1 … Rn) ) C owl:hasKey (P1 … Pm R1 … Rn).
2.6 Declarations
Language Feature Functional Syntax RDF Syntax class Declaration( Class( CN ) ) CN rdf:type owl:Class. datatype Declaration( Datatype( DN ) ) DN rdf:type rdfs:Datatype. object property Declaration( ObjectProperty( PN ) ) PN rdf:type owl:ObjectProperty. data property Declaration( DataProperty( R ) ) R rdf:type owl:DatatypeProperty. annotation property Declaration( AnnotationProperty( A ) ) A rdf:type owl:AnnotationProperty. named individual Declaration( NamedIndividual( aN ) ) aN rdf:type owl:NamedIndividual. 2.7 Annotations
Annotations
Language Feature Functional Syntax RDF Syntax annotation assertion AnnotationAssertion(A s t) s A t. annotation of an axiom
where the axiom in RDF is one or more triples with the same predicate si U tiAXIOM(Annotation(A t) …) _:xi A t.
si U ti. …
_:xi rdf:type owl:Axiom.
_:xi owl:annotatedSource si.
_:xi owl:annotatedProperty U.
_:xi owl:annotatedTarget ti.annotation of an axiom
where the axiom in RDF starts with _:xAXIOM(Annotation(A t) … )
_:x A t.
_:x …. …annotation of another annotation
(the other annotation in RDF starts with s1)Annotation(Annotation(A t) … A1 t1) _:x A t.
s1 A1 t1.
_:x rdf:type owl:Annotation.
_:x owl:annotatedSource s1.
_:x owl:annotatedProperty A1.
_:x owl:annotatedTarget t1.Annotation Properties
Language Feature Functional Syntax RDF Syntax named annotation property A A human-readable name rdfs:label rdfs:label human-readable comment rdfs:comment rdfs:comment additional information rdfs:seeAlso rdfs:seeAlso defining agent rdfs:isDefinedBy rdfs:isDefinedBy version information owl:versionInfo owl:versionInfo deprecation owl:deprecated owl:deprecated backwards compatibility owl:backwardCompatibleWith owl:backwardCompatibleWith incompatibility owl:incompatibleWith owl:incompatibleWith prior version owl:priorVersion owl:priorVersion Annotation Axioms
Language Feature Functional Syntax RDF Syntax annotation subproperties SubAnnotationPropertyOf(A1 A2) A1 rdfs:subPropertyOf A2. annotation property domain AnnotationPropertyDomain(A U) A rdfs:domain U. annotation property range AnnotationPropertyRange(A U) A rdfs:range U. 2.8 Ontologies
Ontologies
Language Feature Functional Syntax RDF Syntax OWL ontology
(importing)*
Ontology([ON [U]]
Import(ON1)...
Annotation(A t)
...
)ON rdf:type owl:Ontology.
[ON owl:versionIRI U.]
ON owl:imports ON1. ...
ON A t.
...prefix declaration** Prefix(p=U) @prefix p U. Note *: in the RDF syntax _:x is used in place of ON if there is no ontology name. ** RDF syntax is in Turtle, other RDF serializations may vary.
3 Built-in Datatypes and Facets
3.1 Built-in Datatypes
Universal Datatype rdfs:Literal Numbers owl:rational owl:real xsd:double xsd:float xsd:decimal xsd:integer xsd:long xsd:int xsd:short xsd:byte xsd:nonNegativeInteger xsd:nonPositiveInteger xsd:positiveInteger xsd:negativeInteger xsd:unsignedLong xsd:unsignedInt xsd:unsignedShort xsd:unsignedByte Strings rdf:PlainLiteral (RDF plain literals) xsd:string xsd:NCName xsd:Name xsd:NMTOKEN xsd:token xsd:language xsd:normalizedString Boolean Values xsd:boolean (value space: true and false) Binary Data xsd:base64Binary xsd:hexBinary IRIs xsd:anyURI Time Instants xsd:dateTime (optional time zone offset) xsd:dateTimeStamp (required time zone offset) XML Literals rdf:XMLLiteral - Note: owl:rational and rdf:XMLLiteral are at Risk in OWL 2.
3.2 Facets
Facet Value Applicable Datatypes Explanation xsd:minInclusive
xsd:maxInclusive
xsd:minExclusive
xsd:maxExclusiveliteral in the corresponding datatype Numbers,
Time InstantsRestricts the value-space to greater than (equal to) or lesser than (equal to) a value xsd:minLength
xsd:maxLength
xsd:lengthNon-negative integer Strings,
Binary Data,
IRIsRestricts the value-space based on the
lengths of the literalsxsd:pattern xsd:string literal as a regular expression Strings,
IRIsRestricts the value space to literals that> match the regular expression rdf:langRange xsd:string literal as a regular expression rdf:PlainLiteral Restricts the value space to literals with language tags that match the regular expression 4 Appendix
4.1 New Features in OWL 2
Class Expressions - local reflexivity (self restriction)
- object and data qualified exact/maximum/minimal cardinality restriction
- universal and existential restriction on n-ary data range
Class Axioms Property Expressions - universal and empty object property
- universal and empty data property
- inverse object property expression
Property Axioms - property chain inclusion
- disjoint object properties
- disjoint data properties
- reflexive, irreflexive, and asymmetric object property.
Data Ranges Assertions Annotation - annotation assertion
- annotation of an axiom or an annotation
- annotation subproperties
- annotation property domain and range
- owl:deprecated annotation property
Extra Built-in Datatypes - owl:rational, owl:real, xsd:dateTimeStamp, rdf:PlainLiteral
Others 4.2 Additional Vocabulary in OWL 2 RDF Syntax
Feature Vocabulary Note data range owl:DataRange deprecated in OWL 2, replaced by rdfs:Datatype membership of a set of pairwise different individuals owl:distinctMembers can alternatively use owl:members ontology property owl:OntologyProperty deprecation owl:DeprecatedClass,
owl:DeprecatedPropertyalternative RDF syntax:
s rdf:type owl:DeprecatedClass . or
s rdf:type owl:DeprecatedProperty .
can be replaced by
s owl:deprecated "true"^^xsd:boolean .
5 Acknowledgments
The starting point for the development of OWL 2 was the OWL1.1 member submission, itself a result of user and developer feedback, and in particular of information gathered during the OWL Experiences and Directions (OWLED) Workshop series. The working group also considered postponed issues from the WebOnt Working Group.
This document has been produced by the OWL Working Group (see below), and its contents reflect extensive discussions within the Working Group as a whole. The editors extend special thanks to Bernardo Cuenca Grau (Oxford University), Christine Golbreich (Université de Versailles St-Quentin and LIRMM), Ivan Herman (W3C/ERCIM), and Bijan Parsia (University of Manchester) for their thorough reviews.
The regular attendees at meetings of the OWL Working Group at the time of publication of this document were: Jie Bao (RPI), Diego Calvanese (Free University of Bozen-Bolzano), Bernardo Cuenca Grau (Oxford University Computing Laboratory), Martin Dzbor (Open University), Achille Fokoue (IBM Corporation), Christine Golbreich (Université de Versailles St-Quentin and LIRMM), Sandro Hawke (W3C/MIT), Ivan Herman (W3C/ERCIM), Rinke Hoekstra (University of Amsterdam), Ian Horrocks (Oxford University Computing Laboratory), Elisa Kendall (Sandpiper Software), Markus Krötzsch (FZI), Carsten Lutz (Universität Bremen), Deborah L. McGuinness (RPI), Boris Motik (Oxford University Computing Laboratory), Jeff Pan (University of Aberdeen), Bijan Parsia (University of Manchester), Peter F. Patel-Schneider (Bell Labs Research, Alcatel-Lucent), Sebastian Rudolph (FZI), Alan Ruttenberg (Science Commons), Uli Sattler (University of Manchester), Michael Schneider (FZI), Mike Smith (Clark & Parsia), Evan Wallace (NIST), Zhe Wu (Oracle Corporation), and Antoine Zimmermann (DERI Galway). We would also like to thank past members of the working group: Jeremy Carroll, Jim Hendler, and Vipul Kashyap.
- This document provides a non-normative quick reference guide to the OWL 2 language. It also provides links to other documents, including the OWL 2 Primer for language introduction and examples, the OWL 2 Structural Specification and Functional Syntax document for more details of the functional syntax, and the OWL 2 New Features and Rationale document for new feature descriptions.
