Necessary conditions for optimization in multiparameter discrete systems

A general first-order dynamic representation for discrete systems with several independent variables is proposed, based on the Dieudonné-Rashevsky form for partial differential equations. This representation does not restrict consideration to causal systems. A minimum principle for such systems is proved, thus extending results known for discrete-time systems to the case of several independent variables. The proof requires only the classical implicit function theorem.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45220/1/10957_2004_Article_BF00934438.pd