TW 423

Nicola Mastronardi, Raf Vandebril, and Marc Van Barel
A Levinson-like algorithm for symmetric positive definite semiseparable plus diagonal matrices

Abstract

In this paper a Levinson-like algorithm is derived for solving symmetric positive definite semiseparable plus diagonal systems of equations. In a first part we solve a Yule-Walker-like system of equations. Based on this O(n) solver an algorithm for a general right-hand side is derived. The new method has a linear complexity and takes 27n-21 operations.

The relation between the algorithm and an upper triangular decomposition of the inverse of the semiseparable plus diagonal matrices is investigated.
Numerical experiments are included.

report.pdf (140K) / mailto: M. Van Barel