numerical roots of a polynomial

*To*: mathgroup at christensen.cybernetics.net*Subject*: [mg1163] numerical roots of a polynomial*From*: Sigurd.Schelstraete at rug.ac.be (Sigurd Schelstraete)*Date*: Sat, 20 May 1995 02:23:23 -0400*Organization*: University of Ghent, Belgium

hello, does anyone know if there exists a package/function that allows one to find (numerically) all n roots of a polynomial of degree n, whether they are real or not? Since NSolve seems to be equivalent to N[Solve], it can not be used for generic polynomials of fifth degree or higher. Also the function FindRoot only allows one to find a single root near a given starting value (which can be complex though). What I would like, is a function that returns the numerical values of all n roots as a list of substitution rules, as does Solve or NSolve. I guess it could be done by successively dividing out a single root found with FindRoot, but I'd rather first hear if anyone out there already has a clear-cut solution to this problem. All answers are appreciated. Greetings, Sigurd Schelstraete University of Gent Belgium