def __get_average_intra_cluster_distance(self, entry):
linear_part_first = list_math_addition(self.linear_sum, entry.linear_sum);<EOL>linear_part_second = linear_part_first;<EOL>linear_part_distance = sum(list_math_multiplication(linear_part_first, linear_part_second));<EOL>general_part_distance = <NUM_LIT> * (self.number_points + entry.number_points) * (self.square_sum + entry.square_sum) - <NUM_LIT> * linear_part_distance;<EOL>return (general_part_distance / ( (self.number_points + entry.number_points) * (self.number_points + entry.number_points - <NUM_LIT:1.0>) )) ** <NUM_LIT:0.5><EOL>
!
        @brief Calculates average intra cluster distance between current and specified clusters.

        @param[in] entry (cfentry): Clustering feature to which distance should be obtained.

        @return (double) Average intra cluster distance.