Some inclusion results based on a generalized version of the Oettli-Prager Theorem

A generalized version of the Oettli-Prager-Theorem is used to derive computable hypernorm bounds for solutions of linear systems from hypernorm bounds for perturbations of the data. It will be shown that the approximations of the interval hull of the solution set of a linear interval system, obtained recently by E. Hansen and J. Rohn, can be considered as special cases of one of the derived estimates. Relations between the Hansen-Rohn inclusions and a somewhat simpler estimate are illustrated by two numerical examples.