# Cross-interactive residual smoothing for global and block Lanczos-type solvers for linear systems with multiple right-hand sides

@article{Aihara2021CrossinteractiveRS, title={Cross-interactive residual smoothing for global and block Lanczos-type solvers for linear systems with multiple right-hand sides}, author={Kensuke Aihara and Akira Imakura and Keiichi Morikuni}, journal={ArXiv}, year={2021}, volume={abs/2106.00284} }

Global and block Krylov subspace methods are efficient iterative solvers for large sparse linear systems with multiple right-hand sides. However, global or block Lanczos-type solvers often exhibit large oscillations in the residual norms and may have a large residual gap relating to the loss of attainable accuracy of the approximations. Conventional residual smoothing schemes suppress these oscillations but cannot improve the attainable accuracy, whereas a recent residual smoothing scheme…

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