On Optimal Banded Preconditioners for the Five-Point Laplacian

  • Authors:
  • Zhanye Tong;Ahmed Sameh

  • Affiliations:
  • -;-

  • Venue:
  • SIAM Journal on Matrix Analysis and Applications
  • Year:
  • 1999

Quantified Score

Hi-index 0.00

Visualization

Abstract

We prove the following theorem, which includes a conjecture by Greenbaum and Rodrigue [[ BIT, 29 (1989), pp. 610--634] as a special case: Let Ah be the five-point Laplace matrix on a unit square for grid size h, and let Mh be any symmetric positive definite preconditioner for Ah with half bandwidth k=O(1). Then the condition number $\kappa(M_h^{-{1\over 2}}A_hM_h^{-{1\over 2}})$ satisfies $\kappa(M_h^{-{1\over 2}}A_hM_h^{-{1\over 2}}) = O(h^{-2}).