Some Remarks on the Elman Estimate for GMRES
نویسندگان
چکیده
Starting from an GMRES error estimate proposed by Elman in terms of the ratio of the smallest eigenvalue of the hermitian part and the norm of some non-symmetric matrix, we propose some asymptotically tighter bound in terms of the same ratio. Here we make use of a recent deep result of Crouzeix et al. on the norm of functions of matrices.
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ورودعنوان ژورنال:
- SIAM J. Matrix Analysis Applications
دوره 27 شماره
صفحات -
تاریخ انتشار 2005