An Approach to Making SPAI and PSAI Preconditioning Effective for Large Irregular Sparse Linear Systems
An Approach to Making SPAI and PSAI Preconditioning Effective for Large Irregular Sparse Linear Systems
We investigate the adaptive sparse approximate inverse (SPAI) and adaptive power sparse approximate inverse (PSAI) preconditioning procedures and shed light on two important features of them: (i) For the large linear system $Ax=b$ with $A$ irregular sparse, i.e., with $A$ having $s$ relatively dense columns, SPAI may be very costly …