An algorithm for checking regularity of interval matrices

Checking regularity (or singularity) of interval matrices is a known NP-har d problem. In this paper a general algorithm for checking regularity/singul arity is presented which is not a priori exponential. The algorithm is base d on a theoretical result according to which regularity may be judged from any single component of the solution set of an associated system of linear interval equations. Numerical experiments (with interval matrices up to the size n = 50) confirm that this approach brings an essential decrease in th e amount of operations needed.