Convergence Properties of Block GMRES and Matrix PolynomialsV
نویسندگان
چکیده
This paper studies convergence properties of the block gmres algorithm when applied to nonsymmetric systems with multiple right-hand sides. A convergence theory is developed based on a representation of the method using matrix-valued polynomials. Relations between the roots of the residual polynomial for block gmres and the matrix "-pseudospectrum are derived, and illustrated with numerical experiments. The role of invariant subspaces in the eeectiveness of block methods is also discussed.
منابع مشابه
Convergence Properties of Block GMRES and Matrix Polynomials
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