package edu.stanford.nlp.semgraph.semgrex.demo;
import edu.stanford.nlp.parser.lexparser.TreebankLangParserParams;
import edu.stanford.nlp.parser.lexparser.EnglishTreebankParserParams;
import edu.stanford.nlp.semgraph.SemanticGraph;
import edu.stanford.nlp.semgraph.SemanticGraphFactory;
import edu.stanford.nlp.semgraph.semgrex.SemgrexMatcher;
import edu.stanford.nlp.semgraph.semgrex.SemgrexPattern;
import edu.stanford.nlp.trees.GrammaticalStructure;
import edu.stanford.nlp.trees.GrammaticalStructureFactory;
import edu.stanford.nlp.trees.Tree;
/**
* A small demo that shows how to convert a tree to a SemanticGraph
* and then run a SemgrexPattern on it
*
* @author John Bauer
*/
public class SemgrexDemo {
public static void main(String[] args) {
String treeString = "(ROOT (S (NP (PRP$ My) (NN dog)) (ADVP (RB also)) (VP (VBZ likes) (S (VP (VBG eating) (NP (NN sausage))))) (. .)))";
// Typically the tree is constructed by parsing or reading a
// treebank. This is just for example purposes
Tree tree = Tree.valueOf(treeString);
// This creates English uncollapsed dependencies as a
// SemanticGraph. If you are creating many SemanticGraphs, you
// should use a GrammaticalStructureFactory and use it to generate
// the intermediate GrammaticalStructure instead
SemanticGraph graph = SemanticGraphFactory.generateUncollapsedDependencies(tree);
// Alternatively, this could have been the Chinese params or any
// other language supported. As of 2014, only English and Chinese
TreebankLangParserParams params = new EnglishTreebankParserParams();
GrammaticalStructureFactory gsf = params.treebankLanguagePack().grammaticalStructureFactory(params.treebankLanguagePack().punctuationWordRejectFilter(), params.typedDependencyHeadFinder());
GrammaticalStructure gs = gsf.newGrammaticalStructure(tree);
System.err.println(graph);
SemgrexPattern semgrex = SemgrexPattern.compile("{}=A <<nsubj {}=B");
SemgrexMatcher matcher = semgrex.matcher(graph);
// This will produce two results on the given tree: "likes" is an
// ancestor of both "dog" and "my" via the nsubj relation
while (matcher.find()) {
System.err.println(matcher.getNode("A") + " <<nsubj " + matcher.getNode("B"));
}
}
}