A note on the normwise perturbation theory for the regular generalized eigenproblem

In this paper, we present a normwise perturbation theory for the regular generalized eigenproblem Ax = Bx, when is a simple and nite eigenvalue, which departs from the classical analysis with the chordal norm 9]. A backward error and a condition number are derived for a choice of exible measure to represent independent perturbations in the matrices A and B. The concept of optimal backward error, associated with an eigenvalue only is also discussed.