Package nltk :: Package parse :: Module api :: Class ParserI

type ParserI

object --+
         |
        ParserI

Known Subclasses:

A processing class for deriving trees that represent possible structures for a sequence of tokens. These tree structures are known as parses. Typically, parsers are used to derive syntax trees for sentences. But parsers can also be used to derive other kinds of tree structure, such as morphological trees and discourse structures.

Subclasses must define:

at least one of: parse(), nbest_parse(), iter_parse(), batch_parse(), batch_nbest_parse(), batch_iter_parse().

Subclasses may define:

grammar()
either prob_parse() or batch_prob_parse() (or both)

Instance Methods

[hide private]

grammar(self)
Returns: The grammar used by this parser.

source code

Tree

parse(self, sent)
Returns: A parse tree that represents the structure of the given sentence, or None if no parse tree is found. source code

list of Tree

nbest_parse(self, sent, n=None)
Returns: A list of parse trees that represent possible structures for the given sentence.

source code

iterator of Tree

iter_parse(self, sent)
Returns: An iterator that generates parse trees that represent possible structures for the given sentence.

source code

ProbDistI of Tree

prob_parse(self, sent)
Returns: A probability distribution over the possible parse trees for the given sentence.

source code

list of Tree

batch_parse(self, sents)
Apply self.parse() to each element of sents. source code

list of list of Tree

batch_nbest_parse(self, sents, n=None)
Apply self.nbest_parse() to each element of sents. source code

list of iterator of Tree

batch_iter_parse(self, sents)
Apply self.iter_parse() to each element of sents. source code

list of ProbDistI of Tree

batch_prob_parse(self, sents)
Apply self.prob_parse() to each element of sents. source code

Deprecated

batch_test(self, filename)

get_parse(self, sent)

get_parse_dict(self, sent)

get_parse_list(self, sent)

get_parse_prob(self, sent)

Method Details

[hide private]

grammar(self)

source code

Returns:: The grammar used by this parser.

parse(self, sent)

source code

Parameters:

sent (list of string) - The sentence to be parsed

Returns: Tree

A parse tree that represents the structure of the given sentence, or None if no parse tree is found. If multiple parses are found, then return the best parse.

nbest_parse(self, sent, n=None)

source code

Parameters:

sent (list of string) - The sentence to be parsed
n (int) - The maximum number of trees to return.

Returns: list of Tree

A list of parse trees that represent possible structures for the given sentence. When possible, this list is sorted from most likely to least likely. If n is specified, then the returned list will contain at most n parse trees.

iter_parse(self, sent)

source code

Parameters:

sent (list of string) - The sentence to be parsed

Returns: iterator of Tree

An iterator that generates parse trees that represent possible structures for the given sentence. When possible, this list is sorted from most likely to least likely.

prob_parse(self, sent)

source code

Parameters:

sent (list of string) - The sentence to be parsed

Returns: ProbDistI of Tree

A probability distribution over the possible parse trees for the given sentence. If there are no possible parse trees for the given sentence, return a probability distribution that assigns a probability of 1.0 to None.

batch_parse(self, sents)

source code

Apply self.parse() to each element of sents. I.e.:

>>> return [self.parse(sent) for sent in sents]

Returns: list of Tree

batch_nbest_parse(self, sents, n=None)

source code

Apply self.nbest_parse() to each element of sents. I.e.:

>>> return [self.nbest_parse(sent, n) for sent in sents]

Returns: list of list of Tree

batch_iter_parse(self, sents)

source code

Apply self.iter_parse() to each element of sents. I.e.:

>>> return [self.iter_parse(sent) for sent in sents]

Returns: list of iterator of Tree

batch_prob_parse(self, sents)

source code

Apply self.prob_parse() to each element of sents. I.e.:

>>> return [self.prob_parse(sent) for sent in sents]

Returns: list of ProbDistI of Tree

batch_test(self, filename)

Decorators:

@deprecated("No longer supported.")

get_parse(self, sent)

Decorators:

@deprecated("Use parse() instead.")

get_parse_dict(self, sent)

Decorators:

@deprecated("Use prob_parse() instead.")

get_parse_list(self, sent)

Decorators:

@deprecated("Use nbest_parse() instead.")

get_parse_prob(self, sent)

Decorators:

@deprecated("Use prob_parse() instead.")