Source code for nltk.corpus.reader.string_category

# Natural Language Toolkit: String Category Corpus Reader
# Copyright (C) 2001-2022 NLTK Project
# Author: Steven Bird <>
#         Edward Loper <>
# URL: <>
# For license information, see LICENSE.TXT

Read tuples from a corpus consisting of categorized strings.
For example, from the question classification corpus:

NUM:dist How far is it from Denver to Aspen ?
LOC:city What county is Modesto , California in ?
HUM:desc Who was Galileo ?
DESC:def What is an atom ?
NUM:date When did Hawaii become a state ?

from nltk.corpus.reader.api import *

# based on PPAttachmentCorpusReader
from nltk.corpus.reader.util import *

# [xx] Should the order of the tuple be reversed -- in most other places
# in nltk, we use the form (data, tag) -- e.g., tagged words and
# labeled texts for classifiers.
[docs]class StringCategoryCorpusReader(CorpusReader):
[docs] def __init__(self, root, fileids, delimiter=" ", encoding="utf8"): """ :param root: The root directory for this corpus. :param fileids: A list or regexp specifying the fileids in this corpus. :param delimiter: Field delimiter """ CorpusReader.__init__(self, root, fileids, encoding) self._delimiter = delimiter
[docs] def tuples(self, fileids=None): if fileids is None: fileids = self._fileids elif isinstance(fileids, str): fileids = [fileids] return concat( [ StreamBackedCorpusView(fileid, self._read_tuple_block, encoding=enc) for (fileid, enc) in self.abspaths(fileids, True) ] )
def _read_tuple_block(self, stream): line = stream.readline().strip() if line: return [tuple(line.split(self._delimiter, 1))] else: return []