Introduction to Discrete Convex Analysis

Abstract

Discrete convex analysis is a theory that aims at a discrete analogue of convex analysis for nonlinear discrete optimization. Technically it is a nonlinear generalization of matroid/submodular function theory; matroids are generalized to M-convex functions and submodular set functions to L-convex function.This talk consists of two parts: In the first part fundamental concepts and theorems in discrete convex analysis are explained with reference to familiar combinatorial optimization problems like minimum spanning tree, shortest path, and matching. In view of the recent development in submodular function maximization, minimization and maximization algorithms in discrete convex analysis are explained in the second part of the talk. In particular, M-natural concave functions form a subclass of submodular functions that can be maximized in polynomial time.