NLP (version 0.1-6)

CoNLLTextDocument: CoNLL-Style Text Documents

Description

Create text documents from CoNLL-style files.

Usage

CoNLLTextDocument(con, encoding = "unknown", meta = list())

Arguments

con

a connection object or a character string. See scan() for details.

encoding

encoding to be assumed for input strings. See scan() for details.

meta

a named or empty list of document metadata tag-value pairs.

Value

• An object inheriting from "CoNLLTextDocument" and "TextDocument".

Details

CoNLL-style files use an extended tabular format where empty lines separate sentences, and non-empty lines consist of whitespace separated columns giving the word tokens and annotations for these. In principle, these annotations can vary from corpus to corpus: the current version of CoNLLTextDocument() assumes a fixed set of 3 columns giving, respectively, the word token and its POS and chunk tags.

The lines are read from the given connection and split into fields using scan(). From this, a suitable representation of the provided information is obtained, and returned as a CoNLL text document object inheriting from classes "CoNLLTextDocument" and "TextDocument".

There are methods for generics words(), sents(), tagged_words(), tagged_sents(), and chunked_sents() (as well as as.character()) and class "CoNLLTextDocument", which should be used to access the text in such text document objects.

See Also

TextDocument for basic information on the text document infrastructure employed by package NLP.

http://ifarm.nl/signll/conll/ for general information about CoNLL (Conference on Natural Language Learning), the yearly meeting of the Special Interest Group on Natural Language Learning of the Association for Computational Linguistics. http://www.cnts.ua.ac.be/conll2000/chunking/ for the CoNLL 2000 chunking task, and training and test data sets which can be read in using CoNLLTextDocument().