The Analysis of Smoothers for Multigrid Algorithms
نویسندگان
چکیده
The purpose of this paper is to provide a general technique for defining and analyzing smoothing operators for use in multigrid algorithms. The smoothing operators considered are based on subspace decomposition and include point, line, and block versions of Jacobi and Gauss-Seidel iteration as well as generalizations. We shall show that these smoothers will be effective in multigrid algorithms provided that the subspace decomposition satisfies two simple conditions. In many applications, these conditions are trivial to verify.
منابع مشابه
On Hybrid Multigrid-Schwarz Algorithms
J. Lottes and P. Fischer in [J. Sci. Comput., 24:45–78, 2005] studied many smoothers or preconditioners for hybrid Multigrid-Schwarz algorithms for the spectral element method. The behavior of several of these smoothers or preconditioners are analyzed in the present paper. Here it is shown that the Schwarz smoother that best performs in the above reference, is equivalent to a special case of th...
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