Examples of GrammaticalRelation

• edu.stanford.nlp.trees.GrammaticalRelation
  {@code GrammaticalRelation} is used to define astandardized, hierarchical set of grammatical relations, together with patterns for identifying them in parse trees.

  Each GrammaticalRelation has:

  • A String short name, which should be a lowercase abbreviation of some kind (in the fure mainly Universal Dependency names).
  • A String long name, which should be descriptive.
  • A parent in the GrammaticalRelation hierarchy.
  • A {@link Pattern Pattern} calledsourcePattern which matches (parent) nodes from which this GrammaticalRelation could hold. (Note: this is done with the Java regex Pattern matches() predicate. The pattern must match the whole node name, and ^ or $ aren't needed. Tregex constructions like __ do not work. Use ".*" to be applicable at all nodes. This prefiltering is used for efficiency.)
  • A list of zero or more {@link TregexPattern TregexPatterns} called targetPatterns,which describe the local tree structure which must hold between the source node and a target node for the GrammaticalRelation to apply. (Note: {@code tregex}regular expressions match with the {@code find()} method, whileliteral string label descriptions that are not regular expressions must be {@code equals()}.)

  The targetPatterns associated with a GrammaticalRelation are designed as follows. In order to recognize a grammatical relation X holding between nodes A and B in a parse tree, we want to associate with GrammaticalRelation X a {@link TregexPattern TregexPattern} such that:

  • the root of the pattern matches A, and
  • the pattern includes a node labeled "target", which matches B.

  For example, for the grammatical relation PREDICATE which holds between a clause and its primary verb phrase, we might want to use the pattern {@code "S < VP=target"}, in which the root will match a clause and the node labeled "target" will match the verb phrase.

  For a given grammatical relation, the method {@link GrammaticalRelation#getRelatedNodes getRelatedNodes()}takes a Tree node as an argument and attempts to return other nodes which have this grammatical relation to the argument node. By default, this method operates as follows: it steps through the patterns in the pattern list, trying to match each pattern against the argument node, until it finds some matches. If a pattern matches, all matching nodes (that is, each node which corresponds to node label "target" in some match) are returned as a list; otherwise the next pattern is tried.

  For some grammatical relations, we need more sophisticated logic to identify related nodes. In such cases, {@link GrammaticalRelation#getRelatedNodes getRelatedNodes()}can be overridden on a per-relation basis using anonymous subclassing.

  @see GrammaticalStructure @see EnglishGrammaticalStructure @see EnglishGrammaticalRelations @see edu.stanford.nlp.trees.international.pennchinese.ChineseGrammaticalRelations @author Bill MacCartney @author Galen Andrew (refactoring English-specific stuff) @author Ilya Sherman (refactoring annotation-relation pairing, which is now gone)

• org.apache.stanbol.enhancer.nlp.dependency.GrammaticalRelation

Examples of org.apache.stanbol.enhancer.nlp.dependency.GrammaticalRelation