If I have a function which is convex in the hypercube, $[-1,1]^n$ then when would it imply that its restriction to $\{-1,1\}^n$ is submodular?
- It would be helpful is someone can share some specific example calculation! (better if you have examples with spectral norms which is a convex function!)
(..I am implicitly assuming the picture that a function on the Boolean hypercube can always be thought of as a function on the powerset of the set $\{1,2,..,n\}$. The numbers in any element of the powerset specifies the indices of the domain vector which have 1 (and the rest will have -1)...)