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agg April 29, 2004 17:20

Polynomial Root finding
Does anyone know of a numerical/algebraic method to find the largest real root of a polynomial? References are appreciated.

Thank you.

Apurva April 30, 2004 01:06

Re: Polynomial Root finding
Title: Roots of polynomials by ratio of successive derivatives Author(s): Crouse, J. E. (NASA Lewis Research Center, Cleveland, OH, United States); Putt, C. W. (NASA Lewis Research Center, Cleveland, OH, United States) Date: 1972 Citation: NASA-TN-D-6793

versi May 4, 2004 05:42

Re: Polynomial Root finding
have a look at "Numerical Recipes"

agg May 4, 2004 11:46

Re: Polynomial Root finding
Thanks guys,

Let me first explain why I need to solve a polynomial eqn. Reference JFM(2000), vol.415, pp.261-284 "A scale-dependent dynamic model for LES". I want to solve eqn. (3.14) which is a polynomial of degree 5. But I only need the largest, real, positive root. In the paper they solve this using a Newton-Raphson method. I wanted to know if there is a ready-made subroutine that will give me the largest real root.


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