Stability of block LU factorization for block tridiagonal block H-matrices

摘要

By a block representation of LU factorization for a general matrix introduced by Amodio and Mazzia [P. Amodio, F. Mazzia, A new approach to the backward error analysis in the LU factorization algorithm, BIT 39 (1999) 385402], a block representation of block LU factorization for block tridiagonal block H-matrices is obtained and some properties on the factors of the factorization are presented. Perturbation theory for the block LU factorization of block tridiagonal block H-matrices is also considered. Then a rounding error analysis of the block LU factorization for block tridiagonal block H-matrices is given, and some bounds for the growth factor are proposed. Finally, a numerical example is presented to illustrate our theoretical results.