Stability properties of superoptimal preconditioner from numerical range
Che‐Man Cheng, Xiao‐Qing Jin, Yimin Wei · Numerical Linear Algebra with Applications · 2005
Abstract A matrix is said to be stable if the real parts of all the eigenvalues are negative. In this paper, for any matrix An, we give some sufficient and necessary conditions for the stability of superoptimal preconditioner EU(An) proposed by Tyrtyshnikov (SIAM J. Matrix Anal. Appl. 1992; 13:459–473). Copyright © 2005 John Wiley & Sons, Ltd.