nltk.parse.nonprojectivedependencyparser.NonprojectiveDependencyParser

class documentation

class NonprojectiveDependencyParser(object): (source)

Constructor: NonprojectiveDependencyParser(dependency_grammar)

A non-projective, rule-based, dependency parser. This parser will return the set of all possible non-projective parses based on the word-to-word relations defined in the parser's dependency grammar, and will allow the branches of the parse tree to cross in order to capture a variety of linguistic phenomena that a projective parser will not.

Method	`__init__`	Creates a new `NonprojectiveDependencyParser`.
Method	`parse`	Parses the input tokens with respect to the parser's grammar. Parsing is accomplished by representing the search-space of possible parses as a fully-connected directed graph. Arcs that would lead to ungrammatical parses are removed and a lattice is constructed of length n, where n is the number of input tokens, to represent all possible grammatical traversals...
Instance Variable	`_grammar`	Undocumented
Instance Variable	`_graph`	Undocumented

def __init__(self, dependency_grammar): (source) ¶

Creates a new NonprojectiveDependencyParser.

Parameters
dependency_grammar:DependencyGrammar	a grammar of word-to-word relations.

def parse(self, tokens): (source) ¶

Parses the input tokens with respect to the parser's grammar. Parsing is accomplished by representing the search-space of possible parses as a fully-connected directed graph. Arcs that would lead to ungrammatical parses are removed and a lattice is constructed of length n, where n is the number of input tokens, to represent all possible grammatical traversals. All possible paths through the lattice are then enumerated to produce the set of non-projective parses.

param tokens: A list of tokens to parse. type tokens: list(str) return: An iterator of non-projective parses. rtype: iter(DependencyGraph)

_grammar = (source) ¶

Undocumented

_graph = (source) ¶

Undocumented