difference equations;
Lagrangian systems;
Helmholtz's problem;
discrete calculus of variations;
D O I:
10.1080/10236198.2012.754435
中图分类号:
O29 [应用数学];
学科分类号:
070104 ;
摘要:
We derive the discrete version of the classical Helmholtz's condition. Precisely, we state a theorem characterizing second-order finite difference equations admitting a Lagrangian formulation. Moreover, in the affirmative case, we provide the class of all possible Lagrangian formulations.