本例用RBF网络拟合未知函数，预先设定一个非线性函数，假定函数解析式不清楚的情况下，随机产生x1，x2和由这两个变量按上式得出的y。-In this case, using RBF network fitting of the unknown function preset a nonlinear function, assume that function under the condition of analytic expression is not clear, randomly gen