title: KMeans vs. KMeansClustering in tensorflow.contrib
body: <p>According to the documentation of tensorflow there are two classes that relate to Kmeans algorithm. One of them is 
  <a href="https://www.tensorflow.org/api_docs/python/tf/contrib/factorization/KMeans" rel="nofollow noreferrer">tensorflow.contrib.factorization.KMeans</a>
   and the other one is <a href="https://www.tensorflow.org/api_docs/python/tf/contrib/factorization/KMeansClustering" rel="nofollow noreferrer">tensorflow.contrib.factorization.KMeansClustering</a>.
  The documentation states that former is for creating the graph for kmeans clustering but I don't actually get it.
  I want to use kmeans for MNIST dataset to cluster digits then classify them. Which class should I use for my code?</p>