Exact inverse solution techniques for a class of complex valued block two-by-two linear systems

0556739 - ÚGN 2023 RIV NL eng J - Journal Article
Liang, Z.-Z. - Axelsson, Owe
Exact inverse solution techniques for a class of complex valued block two-by-two linear systems.
Numerical Algorithms. Roč. 90, August 2021 (2022), s. 79-98. ISSN 1017-1398. E-ISSN 1572-9265
R&D Projects: GA MŠMT LQ1602
Institutional support: RVO:68145535
Keywords : complex linear systems * schur complement * matrix factorization * time-harmonic parabolic equation
OECD category: Applied mathematics
Impact factor: 2.1, year: 2022
Method of publishing: Limited access
https://link.springer.com/content/pdf/10.1007/s11075-021-01180-z.pdf

By taking a complex factorization of the Schur complement matrix into consideration, we present practical expressions for the inverses of a class of complex valued block two-by-two matrices. Then, based on the obtained practical inverse expressions, some efficient exact inverse solution methods are presented for solving the related linear systems within both iterative refinement and Krylov subspace accelerations. Numerical experiments indicate that in most cases the proposed exact inverse methods perform better than the MINRES and GMRES methods accelerated by some existing efficient preconditioners.
Permanent Link: http://hdl.handle.net/11104/0330901