A Comparison of Various Methods for Computing Bounds for Positive Roots of
Polynomials

Alkiviadis G. Akritas and Panagiotis S. Vigklas
Department of Computer and Communication Engineering
University of Thessaly
Volos, Greece

The recent interest in isolating real roots of polynomials with continued
fractions, has revived interest in computing bounds for _positive_ roots of
polynomials.  Computing such bounds is totally missing in mathematical
education, where emphasis is given on computing bounds on the _absolute_
values of the roots of polynomials.

In this paper we examine the methods of Cauchy, Lagrange and Stefanescu for
computing bounds for _positive_ roots of polynomials and compare their 
performance on various classes of polynomials.