code: public static List<Row> minMaxColumns(DataRowsFacade data, List<String> columns) {
          String[] arr = new String[columns.size()];
          for (int i = 0; i < arr.length; i++)
              arr[i] = columns.get(i);
          return minMaxColumns(data, arr);
      }
docs: Returns the min and max of the given columns
  @param data the data to get the max for
  @param columns the columns to get the
  @return