code: def extract_attribute_array(self, data_array, var_name):
          
          if var_name not in self.attributes.keys():
              self.attributes[var_name] = []
          for t in range(self.times.size):
              self.attributes[var_name].append(data_array[self.i[t], self.j[t]])
docs: Extracts data from a 2D array that has the same dimensions as the grid used to identify the object.
  
          Args:
              data_array: 2D numpy array