By applying Krylov subspace iterative method to solving the matrix equation and Fast Multiple Method to matrix-vector multiplication acceleration,the space and time complexity of the method is reduced to be O(N1.5) as a result.

• 通过引入Krylov子空间迭代算法来求解矩阵方程；并使用快速多极子算法来加速计算矩阵向量积；可以使算法的空间和时间复杂度降为O(N1.；5)