BIT Numerical Mathematics

, Volume 37, Issue 2, pp 333–345 | Cite as

Polynomial root computation by means of the LR algorithm

  • Luca Gemignani
Article
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Abstract

By representing the LR algorithm of Rutishauser and its variants in a polynomial setting, we derive numerical methods for approximating either all of the roots or a numberk of the roots of minimum modulus of a given polynomialp(t) of degreen. These methods share the convergence properties of the LR matrix iteration but, unlike it, they can be arranged to produce parallel and sequential algorithms which are highly efficient especially in the case wherek≪n.

AMS subject classification

65H05 65F15 

Key words

Root-finding algorithms LR matrix iteration 
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Copyright information

© BIT Foundaton 1997

Authors and Affiliations

  • Luca Gemignani
    • 1
  1. 1.Dipartimento di InformaticaUniversità di PisaPisaItaly

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