Pattern is a web mining module for the Python programming language.
It bundles tools for data retrieval (Google + Twitter + Wikipedia API, web spider, HTML DOM parser), text analysis (rule-based shallow parser, WordNet interface, syntactical + semantical n-gram search algorithm, tf-idf + cosine similarity + LSA metrics), clustering and classification (k-means, KNN, SVM), and data visualization (graph networks).
D. Lin. Proceedings of the 17th international conference on Computational linguistics, page 768--774. Morristown, NJ, USA, Association for Computational Linguistics, (1998)