1)convex closure of saddle function,鞍函数的凸闭包2)concave closure of saddle function,鞍函数的凹闭包3)superclosure of concave-convex function,凹凸函数的上闭包4)lower closure of concave-convex function,凹凸函数的下闭包5)convex hull of a function,函数的凸包6)closed convex function,闭凸函数