nltk/nltk — pull request #2 by rsennrich (2011-11-29 10:54:15+00:00)
Title: fix cosine_distance for KMeansClusterer 

see issue 709 http://code.google.com/p/nltk/issues/detail?id=709
in short, cosine_distance is implemented as a similarity metric,
while KMeansClusterer expects a distance metric.