nltk.corpus.reader.BNCCorpusReader

class documentation

class BNCCorpusReader(XMLCorpusReader): (source)

Constructor: BNCCorpusReader(root, fileids, lazy)

Corpus reader for the XML version of the British National Corpus.

For access to the complete XML data structure, use the xml() method. For access to simple word lists and tagged word lists, use words(), sents(), tagged_words(), and tagged_sents().

You can obtain the full version of the BNC corpus at http://www.ota.ox.ac.uk/desc/2554

If you extracted the archive to a directory called BNC, then you can instantiate the reader as:

BNCCorpusReader(root='BNC/Texts/', fileids=r'[A-K]/\w*/\w*\.xml')

Method	`__init__`	No summary
Method	`sents`	No summary
Method	`tagged_sents`	No summary
Method	`tagged_words`	No summary
Method	`words`	No summary
Method	`_views`	A helper function that instantiates BNCWordViews or the list of words/sentences.
Method	`_words`	Helper used to implement the view methods -- returns a list of words or a list of sentences, optionally tagged.
Instance Variable	`_lazy`	Undocumented

Inherited from XMLCorpusReader:

Method	`raw`	Undocumented
Method	`xml`	Undocumented
Instance Variable	`_wrap_etree`	Undocumented

Inherited from CorpusReader (via XMLCorpusReader):

Method	`__repr__`	Undocumented
Method	`abspath`	Return the absolute path for the given file.
Method	`abspaths`	Return a list of the absolute paths for all fileids in this corpus; or for the given list of fileids, if specified.
Method	`citation`	Return the contents of the corpus citation.bib file, if it exists.
Method	`encoding`	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.
Method	`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).
Method	`fileids`	Return a list of file identifiers for the fileids that make up this corpus.
Method	`license`	Return the contents of the corpus LICENSE file, if it exists.
Method	`open`	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.
Method	`readme`	Return the contents of the corpus README file, if it exists.
Class Variable	`root`	Undocumented
Method	`_get_root`	Undocumented
Instance Variable	`_encoding`	The default unicode encoding for the fileids that make up this corpus. If `encoding` is None, then the file contents are processed using byte strings.
Instance Variable	`_fileids`	A list of the relative paths for the fileids that make up this corpus.
Instance Variable	`_root`	The root directory for this corpus.
Instance Variable	`_tagset`	Undocumented

def __init__(self, root, fileids, lazy=True): (source) ¶

overrides nltk.corpus.reader.XMLCorpusReader.__init__

Parameters
root:PathPointer or str	A path pointer identifying the root directory for this corpus. If a string is specified, then it will be converted to a `PathPointer` automatically.
fileids	A list of the files that make up this corpus. This list can either be specified explicitly, as a list of strings; or implicitly, as a regular expression over file paths. The absolute path for each file will be constructed by joining the reader's root to each file name.
lazy	Undocumented
encoding	The default unicode encoding for the files that make up the corpus. The value of `encoding` can be any of the following: - A string: `encoding` is the encoding name for all files. - A dictionary: `encoding[file_id]` is the encoding name for the file whose identifier is `file_id`. If `file_id` is not in `encoding`, then the file contents will be processed using non-unicode byte strings. A list: `encoding` should be a list of `(regexp, encoding)` tuples. The encoding for a file whose identifier is `file_id` will be the `encoding` value for the first tuple whose `regexp` matches the `file_id`. If no tuple's `regexp` matches the `file_id`, the file contents will be processed using non-unicode byte strings. None: the file contents of all files will be processed using non-unicode byte strings.
tagset	The name of the tagset used by this corpus, to be used for normalizing or converting the POS tags returned by the tagged_...() methods.

def sents(self, fileids=None, strip_space=True, stem=False): (source) ¶

Parameters
fileids	Undocumented
strip_space	If true, then strip trailing spaces from word tokens. Otherwise, leave the spaces on the tokens.
stem	If true, then use word stems instead of word strings.
Returns
list(list(str))	the given file(s) as a list of sentences or utterances, each encoded as a list of word strings.

def tagged_sents(self, fileids=None, c5=False, strip_space=True, stem=False): (source) ¶

Parameters
fileids	Undocumented
c5	If true, then the tags used will be the more detailed c5 tags. Otherwise, the simplified tags will be used.
strip_space	If true, then strip trailing spaces from word tokens. Otherwise, leave the spaces on the tokens.
stem	If true, then use word stems instead of word strings.
Returns
list(list(tuple(str,str)))	the given file(s) as a list of sentences, each encoded as a list of `(word,tag)` tuples.

def tagged_words(self, fileids=None, c5=False, strip_space=True, stem=False): (source) ¶

Parameters
fileids	Undocumented
c5	If true, then the tags used will be the more detailed c5 tags. Otherwise, the simplified tags will be used.
strip_space	If true, then strip trailing spaces from word tokens. Otherwise, leave the spaces on the tokens.
stem	If true, then use word stems instead of word strings.
Returns
list(tuple(str,str))	the given file(s) as a list of tagged words and punctuation symbols, encoded as tuples `(word,tag)`.

def words(self, fileids=None, strip_space=True, stem=False): (source) ¶

overrides nltk.corpus.reader.XMLCorpusReader.words

Parameters
fileids	Undocumented
strip_space	If true, then strip trailing spaces from word tokens. Otherwise, leave the spaces on the tokens.
stem	If true, then use word stems instead of word strings.
Returns
list(str)	the given file(s) as a list of words and punctuation symbols.

def _views(self, fileids=None, sent=False, tag=False, strip_space=True, stem=False): (source) ¶

A helper function that instantiates BNCWordViews or the list of words/sentences.

def _words(self, fileid, bracket_sent, tag, strip_space, stem): (source) ¶

Helper used to implement the view methods -- returns a list of words or a list of sentences, optionally tagged.

Parameters
fileid	The name of the underlying file.
bracket_sent	If true, include sentence bracketing.
tag	The name of the tagset to use, or None for no tags.
strip_space	If true, strip spaces from word tokens.
stem	If true, then substitute stems for words.

_lazy = (source) ¶

Undocumented