Multilayer approximate nullspace methods for saddle point systems

We propose a new class of multi-layer iterative schemes for solving sparse linear systems in saddle point structure. The new scheme consist of an iterative preconditioner that is based on the (approximate) nullspace method, combined with an iterative least squares approach and an iterative projection method. We present a theoretical analysis and demonstrate the effectiveness and robustness of the new scheme on sparse matrices from various applications.

💡 Research Summary

The paper introduces a novel multi‑layer iterative framework for solving large sparse saddle‑point (or saddle‑point) linear systems of the form

\