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Unitary polynomial

Let $P$ be a polynomial and be maxroot the maximal modulus of the root of $P$. From $P$ we may derive a polynomial $Q$ such that the roots of $Q$ have a modulus lower or equal to 1 and if $w$ is a root of $Q$ then maxroot$w$ is a root of $P$. The calculation of the coefficients of $Q$ may be done with the procedure

int Unit_Polynom(int Degree,INTERVAL_VECTOR &Coeff,
                double maxroot,INTERVAL_VECTOR &CoeffU)
where Coeff are the coefficients of $P$ and CoeffU the coefficients of $Q$. This procedure returns 1 if the calculation has been successfull, 0 otherwise.

Jean-Pierre Merlet 2012-12-20