title: Build a recommender system in weka
body: <p>I want to build a recommender system that needs to work online. </p>
  
  <p>I have a very large database of music, with about 40 features per song. These need to be clustered and then a few songs need to be suggested based on the current song. </p>
  
  <p>I can cluster the data with Weka with simpleClustering. Do I just take items out of the same cluster for recommendation. Any idea how to do this with weka?</p>
  
  <p>How could I make this an online continuously updating system? Or do there exist services or APIs that offer this?</p>