拟牛顿法，是求解非线性优化问题最有效的方法之一，拟牛顿法的基本思想如下。首先构造 目标函数在当前迭代 的二次模型。-Quasi-Newton method for solving nonlinear optimization problem is one of the most effective way, the basic idea of quasi-Newton method is as follows. First objective function quadratic model in the current iteration.