Residual Smoothing Techniques: Do They Improve the Limiting Accuracy of Iterative Solvers?

0403719 - UIVT-O 20010006 RIV SE eng J - Journal Article
Gutknecht, M. H. - Rozložník, Miroslav
Residual Smoothing Techniques: Do They Improve the Limiting Accuracy of Iterative Solvers?
Bit. Roč. 41, č. 1 (2001), s. 86-114. ISSN 0006-3835. E-ISSN 1572-9125
R&D Projects: GA ČR GA201/98/P108
Institutional research plan: AV0Z1030915
Keywords : iterative methods * residual smoothing * limiting accuracy
Subject RIV: BA - General Mathematics
Impact factor: 0.835, year: 2001

Many iterative methods for solving linear systems produce often residuals whose norms fluctuate rather strongly. Large intermediate residuals are known to reduce the ultimately attainable accuracy of the method. We show that the ultimately attainable accuracy of the smoothed iterates is not higher than that of the primary iterates. Nevertheless, smoothing can be used to produce certain residuals, with higher attainable accuracy than by other frequently used algorithms.
Permanent Link: http://hdl.handle.net/11104/0124013