fmpr / texttk

Text Preprocessing in Python

texttk -- Text Preprocessing in Python

texttk is a Python library for text preprocessing of large corpora, that can be used for topic modelling, text classification, document clustering, information retrieval, etc.

Features

• Removes stopwords, punctuation, HTML tags, accents, rare words, very frequent words, etc.
• Applies stemmer or lemmatizer
• Finds the most relevant bigrams
• Performs named entity recognition
• Tokenizes text
• Generates bag-of-words representations
• Identifies and joins compound words
• Splits documents in sentences

Default preprocessing pipeline ---------

• unescape characters
• remove HTML tags
• strip accents
• join URLs
• join compound words
• space out punctuation
• split documents in sentences
• tag sentences using Stanford NER
• merge named entities as single tokens
• remove punctuation
• convert to lowercase
• find top-100 bigrams using chi-squared
• merge bigrams as single tokens
• tokenize documents
• remove stopwords
• apply stemmer/lemmatizer
• remove rare words
• remove very frequent words
• convert corpus to bag-of-words format

Basic Usage

Basic preprocessing of a corpus and transformation to bag-of-words format:

import texttk
corpus = ... # a list of strings
tp = texttk.TextPreprocesser(decode_error='strict', strip_accents='unicode', ignore_list=[], \
            lowercase=True, remove_html=True, join_urls=True, use_bigrams=True, \
            use_ner=True, stanford_ner_path="<path_here>", use_lemmatizer=False, \
            max_df=0.95, min_df=1, max_features=None)
corpus = tp.preprocess_corpus(corpus)
transformed_corpus, vocab = tp.convert_to_bag_of_words(corpus)

Installation

This software depends on nltk, sklearn and HTMLParser. You must have them installed prior to installing texttk. If you wish to use NER, texttk also requires access to the Stanford NER Java library.

The simple way to install texttk is:

python setup.py install

Copyright (c) 2016 Filipe Rodrigues

This program is free software. You can redistribute it and/or modify it under the terms of the GNU General Public License, version 3, as published by the Free Software Foundation.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

Appropriate reference to this software should be made when describing research in which it played a substantive role, so that it may be replicated and verified by others.