A zero counting symbolic procedure for a class of univariate Pfaffian functions

GABRIELA JERONIMO

Workshop; Algebra, Geometry and Proofs in Symbolic Computation; 2015

Fields Institute

We will present a symbolic procedure to count the exact number of zeros in a real interval for a class of univariate Pfaffian functions.The procedure is based on the construction of a family of Sturm sequences associated to the given function, which is done by means of polynomial subresultant techniques. As it is usual in the literature on the subject, we assume the existence of an oracle to determine the sign a Pfaffian function takes at a real algebraic number.