Cosine similarity and tf-idf

Question

I am confused by the following comment about TF-IDF and Cosine Similarity.

I was reading up on both and then on wiki under Cosine

Answer 1

tf/idf weighting has some cases where they fail and generate NaN error in code while computing. It's very important to read this: http://www.p-value.info/2013/02/when-tfidf-and-cosine-similarity-fail.html