On the use of harmonic Ritz pairs in approximating internal eigenpairs∗
نویسندگان
چکیده
The goal of this paper is to increase our understanding of harmonic Rayleigh– Ritz for real symmetric matrices. We do this by discussing different, though related topics: a priori error analysis, a posteriori error analysis, a comparison with refined Rayleigh–Ritz and the selection of a suitable harmonic Ritz vector.
منابع مشابه
Generalizations of Harmonic and Refined Rayleigh–ritz
Abstract. We investigate several generalizations of the harmonic and refined Rayleigh–Ritz method. These may be practical when one is interested in eigenvalues close to one of two targets (for instance, when the eigenproblem has Hamiltonian structure such that eigenvalues come in pairs or quadruples), or in rightmost eigenvalues close to (for instance) the imaginary axis. Our goal is to develop...
متن کاملA modified harmonic block Arnoldi algorithm with adaptive shifts for large interior eigenproblems
The harmonic block Arnoldi method can be used to find interior eigenpairs of large matrices. Given a target point or shift to which the needed interior eigenvalues are close, the desired interior eigenpairs are the eigenvalues nearest and the associated eigenvectors. However, it has been shown that the harmonic Ritz vectors may converge erratically and even may fail to do so. To do a better job...
متن کاملHarmonic and refined Rayleigh-Ritz for the polynomial eigenvalue problem
After reviewing the harmonic Rayleigh–Ritz approach for the standard and generalized eigenvalue problem, we discuss different extraction processes for subspace methods for the polynomial eigenvalue problem. We generalize the harmonic and refined Rayleigh–Ritz approach, which are new approaches to extract promising approximate eigenpairs from a search space. We give theoretical as well as numeri...
متن کاملHarmonic Rayleigh-ritz for the Multiparameter Eigenvalue Problem
Harmonic extraction methods for the multiparameter eigenvalue problem willbe presented. These techniques are generalizations of their counterparts forthe standard and generalized eigenvalue problem. The methods aim to ap-proximate interior eigenpairs, generally more accurately than the standardextraction does. The process can be combined with any subspace expansionapproa...
متن کاملPii: S0168-9274(01)00132-5
The harmonic Arnoldi method can be used to compute some eigenpairs of a large matrix, and it is more suitable for finding interior eigenpairs. However, the harmonic Ritz vectors obtained by the method may converge erratically and may even fail to converge, so that resulting algorithms may not perform well. To improve convergence, a refined harmonic Arnoldi method is proposed that replaces the h...
متن کامل