波动方程all-at-once系统的快速α循环绝对值预处理
A Fast α-circulant Absolute Value Preconditioner for All-at-once Systems from Wave Equations
徐果 1张建华1
作者信息
- 1. 东华理工大学理学院,330013,南昌
- 折叠
摘要
为了加快预处理MINRES方法求解波动方程all-at-once系统的收敛速度,基于绝对值预处理子和块状三对角Toeplitz预处理子,提出一种新的α循环绝对值预处理子.理论上证明了预处理矩阵可近似分裂成正交矩阵与低秩矩阵的和,且其特征值聚集在±1 附近,保证了预处理MINRES方法的快速收敛性质.数值实验结果进一步表明了新预处理子的有效性.
Abstract
In order to accelerate convergence rate of the preconditioned MINRES method for all-at-once systems from wave equations,we propose a new α-circulant absolute value preconditioner based on the absolute value preconditioners and the block tridiagonal Toeplitz preconditioners.Fur-thermore,we prove that the corresponding preconditioned matrix can be approximately split into the sum of the orthogonal matrix and the low-rank matrix,and its eigenvalues are clustered around±1,which leads to fast convergence rate of the preconditioned MINRES method.Numerical results also demonstrate the effectiveness of the new preconditioner.
关键词
波动方程/all-at-once系统/预处理MINRES/α循环绝对值预处理子Key words
wave equations/all-at-once systems/preconditioned MINRES method/α-circulant ab-solute value preconditioner引用本文复制引用
基金项目
国家自然科学基金(12061009)
江西省自然科学基金面上项目(20202BAB201002)
出版年
2024