これは $0$ で割ることを防ぐためと、IDF値が $0$ になってしまったとき、TF-IDFの値が $0$ になってしまうのを防ぐのが目的のようです。今回の実装はこの定義に則って実装してみます。 実装 サンプル文書は以下とします。(テキトーな文章で申し訳ございません...) D = [ ["hoge", "fuga", "foo", "bar"], ["hoge", "foo", "hogehoge", "bar"], ["fuga","foofoo","barhoge", "bar"], ["foo", "hoge"], ["nyaa", "hogehoge","bar", "foo", "nyaa"], ["foo","hoge","barhoge","foo","foo"] ] corpus = [] for w in D: corpus.append(" ".join(w)) t
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