New modified shift-splitting preconditioners for non-symmetric saddle point problems (Q2189318)

The authors consider non-symmetric saddle point linear systems, with a positive definite \((1, 1)\) block \(A\). They propose a shift-splitting preconditioner, according to a decomposition of \(A\) into the sum of a (dominant) positive definite matrix and a skew-symmetric one. They study the convergence properties of the iteration produced by the preconditioners, as well as some numerical experiments and comparisons with other methods.