code: public ChunkFrequency query(Region region, Path filePath, int windowSize) {
          return query(region, filePath, windowSize, mean());
      }
docs: Query values for the given region and file. Values are grouped according to the windowSize, and then a mean
  value is computed.
  
  @param region        Region target
  @param filePath      File target
  @param windowSize    Group size of values, the mean is computed for those values
  @return              A chunk frequency region with the mean values