最优化问题本质是一个求极值问题，几乎所有类型的优化问题都可概括为如下模型：给定一个集合（可行集）和该集合上的一个函数（目标函数），要计算此函数在集合上的极值。-Optimization problem is an extremum nature of the problem, almost all types of optimization models can be summarized as follows: given a set of (feasible set) and a function on the set (objective function), to calculate this function in the set the extreme.