nltk.corpus.reader.conll module

Read CoNLL-style chunk fileids.

class nltk.corpus.reader.conll.ConllChunkCorpusReader

Bases: ConllCorpusReader

A ConllCorpusReader whose data file contains three columns: words, pos, and chunk.

__init__(root, fileids, chunk_types, encoding='utf8', tagset=None, separator=None)

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.

• 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.

class nltk.corpus.reader.conll.ConllCorpusReader

Bases: CorpusReader

A corpus reader for CoNLL-style files. These files consist of a series of sentences, separated by blank lines. Each sentence is encoded using a table (or “grid”) of values, where each line corresponds to a single word, and each column corresponds to an annotation type. The set of columns used by CoNLL-style files can vary from corpus to corpus; the ConllCorpusReader constructor therefore takes an argument, columntypes, which is used to specify the columns that are used by a given corpus. By default columns are split by consecutive whitespaces, with the separator argument you can set a string to split by (e.g. ' ').

@todo: Add support for reading from corpora where different

parallel files contain different columns.

@todo: Possibly add caching of the grid corpus view? This would

allow the same grid view to be used by different data access methods (eg words() and parsed_sents() could both share the same grid corpus view object).

@todo: Better support for -DOCSTART-. Currently, we just ignore

it, but it could be used to define methods that retrieve a document at a time (eg parsed_documents()).

CHUNK = 'chunk'

column type for chunk structures

COLUMN_TYPES = ('words', 'pos', 'tree', 'chunk', 'ne', 'srl', 'ignore')

A list of all column types supported by the conll corpus reader.

IGNORE = 'ignore'

column type for column that should be ignored

NE = 'ne'

column type for named entities

POS = 'pos'

column type for part-of-speech tags

SRL = 'srl'

column type for semantic role labels

TREE = 'tree'

column type for parse trees

WORDS = 'words'

column type for words

__init__(root, fileids, columntypes, chunk_types=None, root_label='S', pos_in_tree=False, srl_includes_roleset=True, encoding='utf8', tree_class=<class 'nltk.tree.tree.Tree'>, tagset=None, separator=None)

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.

• 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.

chunked_sents(fileids=None, chunk_types=None, tagset=None)

chunked_words(fileids=None, chunk_types=None, tagset=None)

iob_sents(fileids=None, tagset=None)

Returns

a list of lists of word/tag/IOB tuples

Return type

list(list)

Parameters

fileids (None or str or list) – the list of fileids that make up this corpus

iob_words(fileids=None, tagset=None)

Returns

a list of word/tag/IOB tuples

Return type

list(tuple)

Parameters

fileids (None or str or list) – the list of fileids that make up this corpus

parsed_sents(fileids=None, pos_in_tree=None, tagset=None)

sents(fileids=None)

srl_instances(fileids=None, pos_in_tree=None, flatten=True)

srl_spans(fileids=None)

tagged_sents(fileids=None, tagset=None)

tagged_words(fileids=None, tagset=None)

words(fileids=None)

class nltk.corpus.reader.conll.ConllSRLInstance

Bases: object

An SRL instance from a CoNLL corpus, which identifies and providing labels for the arguments of a single verb.

__init__(tree, verb_head, verb_stem, roleset, tagged_spans)

arguments

A list of (argspan, argid) tuples, specifying the location and type for each of the arguments identified by this instance. argspan is a tuple start, end, indicating that the argument consists of the words[start:end].

pprint()

tagged_spans

A list of (span, id) tuples, specifying the location and type for each of the arguments, as well as the verb pieces, that make up this instance.

tree

The parse tree for the sentence containing this instance.

verb

A list of the word indices of the words that compose the verb whose arguments are identified by this instance. This will contain multiple word indices when multi-word verbs are used (e.g. ‘turn on’).

verb_head

The word index of the head word of the verb whose arguments are identified by this instance. E.g., for a sentence that uses the verb ‘turn on,’ verb_head will be the word index of the word ‘turn’.

words

A list of the words in the sentence containing this instance.

class nltk.corpus.reader.conll.ConllSRLInstanceList

Bases: list

Set of instances for a single sentence

__init__(tree, instances=())

pprint(include_tree=False)