Residuals of refined projection methods for large matrix eigenproblems (Q5948754)

To compute some eigenpairs of large matrices, refined projection methods have been proposed by the author. In practice, the residual norm of an approximate eigenpair is generally used to test a convergence of the computed eigenpair obtained by a refined projection method. In this paper, an a priori error bound for the residual norm of an approximate eigenpair computed by the residual projection method in terms of the deviations is established. It is interesting and meaningful in better understanding the method.