Factorized sparse approximate inverse preconditionings. IV: Simple approaches to rising efficiency
L. Yu. Kolotilina, A. A. Nikishin, A. Yu. Yeremin · Numerical Linear Algebra with Applications · 1999
This paper continues the theoretical and numerical study of the so-called factorized sparse approximate inverse (FSAI) preconditionings of symmetric positive-definite matrices and considers two new approaches to improving them. The first one is based on the a posteriori sparsification of an already constructed FSAI preconditioner, whereas the second one amounts to applying another FSAI preconditioning to an already preconditioned matrix. Numerical results for sample FE problems from structural mechanics are presented. Copyright © 1999 John Wiley & Sons, Ltd.