code: def __calculate_estimation(self):
          
          estimation = 0.0
          for index_cluster in range(0, len(self.__clusters)):
              cluster = self.__clusters[index_cluster]
              index_medoid = self.__current[index_cluster]
              for index_point in cluster:
                  estimation += euclidean_distance_square(self.__pointer_data[index_point], self.__pointer_data[index_medoid])
          
          return estimation
docs: !
          @brief Calculates estimation (cost) of the current clusters. The lower the estimation,
                 the more optimally configuration of clusters.
          
          @return (double) estimation of current clusters.