code: private void updateMeta(Record r) {
          for(Map.Entry<Object, Object> entry : r.getX().entrySet()) {
              Object column = entry.getKey();
              Object value = entry.getValue();
  
              if(value!=null) {
                  data.xDataTypes.putIfAbsent(column, TypeInference.getDataType(value));
              }
          }
  
          if(data.yDataType == null) {
              Object value = r.getY();
              if(value!=null) {
                  data.yDataType = TypeInference.getDataType(r.getY());
              }
          }
      }
docs: Updates the meta data of the Dataframe using the provided Record.
  The Meta-data include the supported columns and their DataTypes.
  
  @param r