TY - JOUR T1 - Iterative Methods with Preconditioners for Indefinite Systems AU - Ren , Wei-Qing AU - Zhao , Jin-Xi JO - Journal of Computational Mathematics VL - 1 SP - 89 EP - 96 PY - 1999 DA - 1999/02 SN - 17 DO - http://doi.org/ UR - https://global-sci.org/intro/article_detail/jcm/9084.html KW - Generalized condition number, Indefinite systems, Factorization method. AB -

For the sparse linear equations $Kx=b$, where $K$ arising from optimization and discretization of some PDEs is symmetric and indefinite, it is shown that the $L \overline{L}^T$ factorization can be used to provide an "exact" preconditioner for SYMMLQ and UZAWA algorithms. "Inexact" preconditioner derived from approximate factorization is used in the numerical experiments.