what is document cluster what is tf-idf document cluster what feature represents clustering document features what feature is used for clustering textual documents what are other features for documents that are used for clustering textual documents? what other features do idfs have why are other documents used what is clustering used for what is clustering used for what is tf-idf used for what is clustering feature representations what is another form of clustering used for what are other features for documents that are used for clustering textual documents? what features do clusters use for documents what are other features than tf-idf for clustering other document features what are different tf-idf functions what is tf-idf used for clustering what is tf-idf used for