An Implementation of the QMR Method Based on Coupled Two-Term Recurrences
An Implementation of the QMR Method Based on Coupled Two-Term Recurrences
Recently, the authors proposed a new Krylov subspace iteration, the quasi-minimal residual (QMR) algorithm, for solving non-Hermitian linear systems. In the original implementation of the QMR method, the Lanczos process with look-ahead is used to generate basis vectors for the underlying Krylov subspaces. In the Lanczos algorithm, these basis vectors …