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arXiv · 2610.17940

Block diagonal preconditioners for arrow-shaped multiple saddle-point linear systems

Luca Bergamaschi·Michele Bergamaschi
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Abstract

We consider multiple saddle-point linear systems with block-arrow structure. We analyze exact and inexact Schur complement based block diagonal preconditioner, by characterizing the eigenvalues of the preconditioned matrices in terms of the zeros of specific rational functions. Numerical results onto large tests coming from liquid crystal modeling and PDE-constrained optimization validate the obtained eigenvalue bounds

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Luca Bergamaschi, Michele Bergamaschi. 2026-10-13. Block diagonal preconditioners for arrow-shaped multiple saddle-point linear systems. https://arxiv.org/abs/2610.17940

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