English

The stability of split-preconditioned FGMRES in four precisions

Numerical Analysis 2024-05-29 v2 Numerical Analysis

Abstract

We consider the split-preconditioned FGMRES method in a mixed precision framework, in which four potentially different precisions can be used for computations with the coefficient matrix, application of the left preconditioner, application of the right preconditioner, and the working precision. Our analysis is applicable to general preconditioners. We obtain bounds on the backward and forward errors in split-preconditioned FGMRES. Our analysis further provides insight into how the various precisions should be chosen; under certain assumptions, a suitable selection guarantees a backward error on the order of the working precision.

Keywords

Cite

@article{arxiv.2303.11901,
  title  = {The stability of split-preconditioned FGMRES in four precisions},
  author = {Erin Carson and Ieva Daužickaitė},
  journal= {arXiv preprint arXiv:2303.11901},
  year   = {2024}
}