code: @SuppressWarnings("unused")
      private int cordToIndex(DataPointPair<Integer> dataPoint)
      {
          DataPoint dp = dataPoint.getDataPoint();
          int index = 0;
          for(int i = 0; i < dimSize.length; i++)
              index = dp.getCategoricalValue(realIndexToCatIndex[i]) + dimSize[i]*index;
          return index;
      }
docs: Computes the index into the {@link #countArray} using the given data point
  @param dataPoint the data point to get the index of
  @return the index for the given data point