code: function setUpDataStore(dataStore, labels, dataLength) {
      var i
        ;
      for (i = 0; i < dataLength; i++) {
        dataStore[i] = {
            words: {}
          , labels: {}
        };
        labels.forEach(function (label) {
          dataStore[i].labels[label] = 0;
        });
      }
    }
docs: Set up structure of the datastore.