Numerische Mathematik

, Volume 14, Issue 3, pp 252–263

A three-stage variable-shift iteration for polynomial zeros and its relation to generalized rayleigh iteration

Authors

  • M. A. Jenkins
    • Stanford University
    • Queens University
  • J. F. Traub
    • Bell Telephone Laboratories, Incorporated
Article

DOI: 10.1007/BF02163334

Cite this article as:
Jenkins, M.A. & Traub, J.F. Numer. Math. (1970) 14: 252. doi:10.1007/BF02163334

Summary

We introduce a new three-stage process for calculating the zeros of a polynomial with complex coefficients. The algorithm is similar in spirit to the two stage algorithms studied by Traub in a series of papers. We prove that the mathematical algorithm always converges and show that the rate of convergence of the third stage is faster than second order. To obtain additional insight we recast the problem and algorithm into matrix form. The third stage is inverse iteration with the companion matrix, followed by generalized Rayleigh iteration.

Copyright information

© Springer-Verlag 1970