POSITIVE SEMIDEFINITENESS OF DISCRETE QUADRATIC FUNCTIONALS
POSITIVE SEMIDEFINITENESS OF DISCRETE QUADRATIC FUNCTIONALS
Abstract We consider symplectic difference systems, which contain as special cases linear Hamiltonian difference systems and Sturm–Liouville difference equations of any even order. An associated discrete quadratic functional is important in discrete variational analysis, and while its positive definiteness has been characterized and is well understood, a characterization of its …