In the last decade many efficient iterative solvers for n × n Hermitian positive definite Toeplitz systems have been devised. Many of them are based on band Toeplitz preconditioners: they are optimal but require the knowledge of the zeros of the underlying generating function. In some cases this information is available and in some cases is not. In  an economic numerical procedure for finding these zeros within a given precision has been devised. Here we provide conditions on the approximation error of these zeros in order to maintain the optimality that is a convergence rate independent of the dimension n of the considered linear systems.
|Titolo:||Practical band Toeplitz preconditioning and boundary layer effects|
|Data di pubblicazione:||2003|
|Appare nelle tipologie:||Articolo su Rivista|