RDF::Reasoner
A partial RDFS/OWL/schema.org reasoner for RDF.rb.
Description
Reasons over RDFS/OWL vocabularies and schema.org to generate statements which are entailed based on base RDFS/OWL rules along with vocabulary information. It can also be used to ask specific questions, such as if a given object is consistent with the vocabulary ruleset. This can be used to implement SPARQL Entailment Regimes and RDF Schema entailment.
Features
- Entail
rdfs:subClassOf
generating an array of terms which are ancestors of the subject. - Entail
rdfs:subPropertyOf
generating an array of terms which are ancestors of the subject. - Entail
rdfs:domain
andrdfs:range
addingrdf:type
assertions on the subject or object. - Inverse
rdfs:subClassOf
entailment, to find descendant classes of the subject term. - Inverse
rdfs:subPropertyOf
entailment, to find descendant properties of the subject term. - Entail
owl:equivalentClass
generating an array of terms equivalent to the subject. - Entail
owl:equivalentProperty
generating an array of terms equivalent to the subject. domainCompatible?
determines if a particular resource is compatible with the domain definition of a given predicate, based on the intersection of entailed subclasses with the property domain.rangeCompatible?
determines if a particular resource is compatible with the range definition of a given predicate, based on the intersection of entailed subclasses or literal types with the property domain.- adds
entail
andlint
commands to therdf
command line interface
Domain and Range entailment include specific rules for schema.org vocabularies.
- A plain literal is an acceptable value for any property.
- If
resource
is of typeschema:Role
,resource
is domain acceptable if any other resource referencesresource
using the same property. - If
resource
is of typeschema:Role
, it is range acceptable if it has the same property with an acceptable value. - If
resource
is of typerdf:List
(must be previously entailed), it is range acceptable if all members of the list are otherwise range acceptable on the same property.
Limiting vocabularies used for reasoning
As loading vocabularies can dominate processing time, the RDF::Vocabulary.limit_vocabs
method can be used to set a specific set of vocabularies over which to reason. For example:
RDF::Vocabulary.limit_vocabs(:rdf, :rdf, :schema)
will limit the vocabularies which are returned from RDF::Vocabulary.each
, which is used for reasoning and other operations over vocabularies and terms.
Examples
Determine super-classes of a class
require 'rdf/reasoner'
RDF::Reasoner.apply(:rdfs)
term = RDF::Vocabulary.find_term("http://xmlns.com/foaf/0.1/Person")
term.entail(:subClassOf)
# => [
foaf:Agent,
http://www.w3.org/2000/10/swap/pim/contact#Person,
geo:SpatialThing,
foaf:Person
]
Determine sub-classes of a class
require 'rdf/reasoner'
RDF::Reasoner.apply(:rdfs)
term = RDF::Vocab::FOAF.Person
term.entail(:subClass) # => [foaf:Person, mo:SoloMusicArtist]
Determine if a resource is compatible with the domains of a property
require 'rdf/reasoner'
require 'rdf/turtle'
RDF::Reasoner.apply(:rdfs)
graph = RDF::Graph.load("etc/doap.ttl")
subj = RDF::URI("https://rubygems.org/gems/rdf-reasoner")
RDF::Vocab::DOAP.name.domain_compatible?(subj, graph) # => true
Determine if a resource is compatible with the ranges of a property
require 'rdf/reasoner'
require 'rdf/turtle'
RDF::Reasoner.apply(:rdfs)
graph = RDF::Graph.load("etc/doap.ttl")
obj = RDF::Literal(Date.new)
RDF::Vocab::DOAP.created.range_compatible?(obj, graph) # => true
Perform equivalentClass entailment on a graph
require 'rdf/reasoner'
require 'rdf/turtle'
RDF::Reasoner.apply(:owl)
graph = RDF::Graph.load("etc/doap.ttl")
graph.entail!(:equivalentClass)
Yield all entailed statements for all entailment methods
require 'rdf/reasoner'
require 'rdf/turtle'
RDF::Reasoner.apply(:rdfs, :owl)
graph = RDF::Graph.load("etc/doap.ttl")
graph.enum_statement.entail.count # >= graph.enum_statement.count
Lint an expanded graph
require 'rdf/reasoner'
require 'rdf/turtle'
RDF::Reasoner.apply(:rdfs, :owl)
graph = RDF::Graph.load("etc/doap.ttl")
graph.entail!
= graph.lint
.each do |kind, |
.each do |term, |
[:output].puts "#{kind} #{term}"
.each {|m| [:output].puts " #{m}"}
end
end
Command-Line interface
The rdf
command-line interface is extended with entail
and lint
commands. Entail
can be used in combination, with serialize
to generate an output graph representation including entailed triples.
Dependencies
Change Log
Mailing List
Authors
Contributing
- Do your best to adhere to the existing coding conventions and idioms.
- Don't use hard tabs, and don't leave trailing whitespace on any line.
Before committing, run
git diff --check
to make sure of this. - Do document every method you add using YARD annotations. Read the tutorial or just look at the existing code for examples.
- Don't touch the
.gemspec
,VERSION
orAUTHORS
files. If you need to change them, do so on your private branch only. - Do feel free to add yourself to the
CREDITS
file and the corresponding list in the theREADME
. Alphabetical order applies. - Do note that in order for us to merge any non-trivial changes (as a rule of thumb, additions larger than about 15 lines of code), we need an explicit public domain dedication on record from you, which you will be asked to agree to on the first commit to a repo within the organization. Note that the agreement applies to all repos in the Ruby RDF organization.
License
This is free and unencumbered public domain software. For more information, see https://unlicense.org/ or the accompanying UNLICENSE file.