nltk.corpus.reader.ChunkedCorpusReader

class nltk.corpus.reader.ChunkedCorpusReader

Bases: CorpusReader

Reader for chunked (and optionally tagged) corpora. Paragraphs are split using a block reader. They are then tokenized into sentences using a sentence tokenizer. Finally, these sentences are parsed into chunk trees using a string-to-chunktree conversion function. Each of these steps can be performed using a default function or a custom function. By default, paragraphs are split on blank lines; sentences are listed one per line; and sentences are parsed into chunk trees using nltk.chunk.tagstr2tree.

__init__(root, fileids, extension='', str2chunktree=<function tagstr2tree>, sent_tokenizer=RegexpTokenizer(pattern='\n', gaps=True, discard_empty=True, flags=re.UNICODE|re.MULTILINE|re.DOTALL), para_block_reader=<function read_blankline_block>, encoding='utf8', tagset=None)

Parameters

• root – The root directory for this corpus.

• fileids – A list or regexp specifying the fileids in this corpus.

words(fileids=None)

Returns

the given file(s) as a list of words and punctuation symbols.

Return type

list(str)

sents(fileids=None)

Returns

the given file(s) as a list of sentences or utterances, each encoded as a list of word strings.

Return type

list(list(str))

paras(fileids=None)

Returns

the given file(s) as a list of paragraphs, each encoded as a list of sentences, which are in turn encoded as lists of word strings.

Return type

list(list(list(str)))

tagged_words(fileids=None, tagset=None)

Returns

the given file(s) as a list of tagged words and punctuation symbols, encoded as tuples (word,tag).

Return type

list(tuple(str,str))

tagged_sents(fileids=None, tagset=None)

Returns

the given file(s) as a list of sentences, each encoded as a list of (word,tag) tuples.

Return type

list(list(tuple(str,str)))

tagged_paras(fileids=None, tagset=None)

Returns

the given file(s) as a list of paragraphs, each encoded as a list of sentences, which are in turn encoded as lists of (word,tag) tuples.

Return type

list(list(list(tuple(str,str))))

chunked_words(fileids=None, tagset=None)

Returns

the given file(s) as a list of tagged words and chunks. Words are encoded as (word, tag) tuples (if the corpus has tags) or word strings (if the corpus has no tags). Chunks are encoded as depth-one trees over (word,tag) tuples or word strings.

Return type

list(tuple(str,str) and Tree)

chunked_sents(fileids=None, tagset=None)

Returns

the given file(s) as a list of sentences, each encoded as a shallow Tree. The leaves of these trees are encoded as (word, tag) tuples (if the corpus has tags) or word strings (if the corpus has no tags).

Return type

list(Tree)

chunked_paras(fileids=None, tagset=None)

Returns

the given file(s) as a list of paragraphs, each encoded as a list of sentences, which are in turn encoded as a shallow Tree. The leaves of these trees are encoded as (word, tag) tuples (if the corpus has tags) or word strings (if the corpus has no tags).

Return type

list(list(Tree))

abspath(fileid)

Return the absolute path for the given file.

Parameters

fileid (str) – The file identifier for the file whose path should be returned.

Return type

PathPointer

abspaths(fileids=None, include_encoding=False, include_fileid=False)

Return a list of the absolute paths for all fileids in this corpus; or for the given list of fileids, if specified.

Parameters

• fileids (None or str or list) – Specifies the set of fileids for which paths should be returned. Can be None, for all fileids; a list of file identifiers, for a specified set of fileids; or a single file identifier, for a single file. Note that the return value is always a list of paths, even if fileids is a single file identifier.

• include_encoding – If true, then return a list of (path_pointer, encoding) tuples.

Return type

list(PathPointer)

citation()

Return the contents of the corpus citation.bib file, if it exists.

encoding(file)

Return the unicode encoding for the given corpus file, if known. If the encoding is unknown, or if the given file should be processed using byte strings (str), then return None.

ensure_loaded()

Load this corpus (if it has not already been loaded). This is used by LazyCorpusLoader as a simple method that can be used to make sure a corpus is loaded – e.g., in case a user wants to do help(some_corpus).

fileids()

Return a list of file identifiers for the fileids that make up this corpus.

license()

Return the contents of the corpus LICENSE file, if it exists.

open(file)

Return an open stream that can be used to read the given file. If the file’s encoding is not None, then the stream will automatically decode the file’s contents into unicode.

Parameters

file – The file identifier of the file to read.

raw(fileids=None)

Parameters

fileids – A list specifying the fileids that should be used.

Returns

the given file(s) as a single string.

Return type

str

readme()

Return the contents of the corpus README file, if it exists.

property root

The directory where this corpus is stored.

Type

PathPointer