Quasiseparable LU Decay Bounds for Inverses of Banded Matrices
Paola Boito, Yuli Eidelman · Numerical Linear Algebra with Applications · 2025
ABSTRACT We develop new, easily computable exponential decay bounds for inverses of banded matrices, based on the quasiseparable representation of Green matrices. The bounds rely on a diagonal dominance hypothesis and do not require explicit spectral information. Numerical experiments and comparisons show that these new bounds can be advantageous, especially for nonsymmetric or symmetric indefinite matrices.