Numerical Analysis Seminar Talk, October 23, 1996

Speaker: Professor Suely Oliveira
Department of Computer Science, Texas A&M University
Title: New Chasing Algorithms for Transforming Arrowhead Matrices into Tridiagonal Form
Time: 4:00pm, Wednesday, October 23, 1996
Place: 503 Blocker

Abstract:

Chasing algorithms are commonly used to find eigenvalues of tridiagonal matrices. They can also be used to transform matrices to tridiagonal form, such as Rutishauser's algorithm for tridiagonalizing banded matrices, Gragg and Harrod's improved version of it, and recently Zha's algorithm for tridiagonalizing arrowhead matrices. All of these methods use the same standard chasing step. Using a graphical theoretical approach, we propose a new chasing algorithm for transforming arrowhead matrices into Tridiagonal form. Although this algorithm has the same sequential computational complexity and backward error properties as the old algorithms, it is better suited for a pipelined approach. The parallel algorithm for this new chasing method is described, with performance results on the Paragon and nCUBE. Comparison results between the old and the new algorithms will be also shown.

Numerical Analysis Seminars

Last revised: 10/21/96 By: Tong.Sun@math.tamu.edu