BP_for_4

代码说明：

  使用神经网络实现对函数sin(x1)/x1*sin(x2)/x2的模拟，代码为matlab代码，输入为二维数组，输出为一个数，结果误差为0.225左右,(Using neural networks to function sin (x1) Analog/x1* sin (x2)/x2, the code for matlab code, enter a two-dimensional array, the output is a number, the result error is about 0.225,)