On the Construction of Deflation-Based Preconditioners
نویسندگان
چکیده
In this article we introduce new bounds on the e ective condition number of de ated and preconditioned-de ated symmetric positive de nite linear systems. For the case of a subdomain de ation such as that of Nicolaides (1987), these theorems can provide direction in choosing a proper decomposition into subdomains. If grid re nement is done keeping the subdomain grid resolution xed, the condition number is insensitive to the grid size. Subdomain de ation is very easy to implement and has been parallelized on a distributed memory system with only a small amount of additional communication. Numerical experiments for a steady-state convection-di usion problem are included.
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عنوان ژورنال:
- SIAM J. Scientific Computing
دوره 23 شماره
صفحات -
تاریخ انتشار 2001