nltk.corpus.reader.PlaintextCorpusReader

class nltk.corpus.reader.PlaintextCorpusReader[source]

Bases: CorpusReader

Reader for corpora that consist of plaintext documents. Paragraphs are assumed to be split using blank lines. Sentences and words can be tokenized using the default tokenizers, or by custom tokenizers specified as parameters to the constructor.

This corpus reader can be customized (e.g., to skip preface sections of specific document formats) by creating a subclass and overriding the CorpusView class variable.

CorpusView

alias of StreamBackedCorpusView

__init__(root, fileids, word_tokenizer=WordPunctTokenizer(pattern='\\w+|[^\\w\\s]+', gaps=False, discard_empty=True, flags=re.UNICODE|re.MULTILINE|re.DOTALL), sent_tokenizer=<nltk.tokenize.punkt.PunktSentenceTokenizer object>, para_block_reader=<function read_blankline_block>, encoding='utf8')[source]

Construct a new plaintext corpus reader for a set of documents located at the given root directory. Example usage:

>>> root = '/usr/local/share/nltk_data/corpora/webtext/'
>>> reader = PlaintextCorpusReader(root, '.*\.txt')
Parameters

  • root – The root directory for this corpus.

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

  • word_tokenizer – Tokenizer for breaking sentences or paragraphs into words.

  • sent_tokenizer – Tokenizer for breaking paragraphs into words.

  • para_block_reader – The block reader used to divide the corpus into paragraph blocks.

words(fileids=None)[source]
Returns

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

Return type

list(str)

sents(fileids=None)[source]
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)[source]
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)))

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