Title
Convergence of Restarted Krylov Subspace Methods for Stieltjes Functions of Matrices.
Abstract
To approximate f(A)b-the action of a matrix function on a vector-by a Krylov subspace method, restarts may become mandatory due to storage requirements for the Arnoldi basis or due to the growing computational complexity of evaluating f on a Hessenberg matrix of growing size. A number of restarting methods have been proposed in the literature in recent years and there has been substantial algorithmic advancement concerning their stability and computational efficiency. However, the question under which circumstances convergence of these methods can be guaranteed has remained largely unanswered. In this paper we consider the class of Stieltjes functions and a related class, which contain important functions like the (inverse) square root and the matrix logarithm. For these classes of functions we present new theoretical results which prove convergence for Hermitian positive definite matrices A and arbitrary restart lengths. We also propose a modification of the Arnoldi approximation which guarantees convergence for the same classes of functions and any restart length if A is not necessarily Hermitian but positive real (i.e., has its field of values in the right half-plane).
Year
DOI
Venue
2014
10.1137/140973463
SIAM JOURNAL ON MATRIX ANALYSIS AND APPLICATIONS
Keywords
DocType
Volume
matrix functions,Krylov subspace methods,restarted Arnoldi method,conjugate gradient method,shifted linear systems,harmonic Ritz values
Journal
35
Issue
ISSN
Citations 
4
0895-4798
5
PageRank 
References 
Authors
0.57
6
3
Name
Order
Citations
PageRank
Andreas Frommer17911.58
Stefan Güttel2423.06
Marcel Schweitzer3213.69