中文说明：很好用的BP神经网络系统，对阈值和域值的搜索做了很好的选取，隐含层的设计也很巧妙，希望大家多多学习，共同学习。
English Description：
Good use of the BP neural network system, the threshold and domain value of the search has done a good selection, hidden layer design is also very clever, I hope you learn more, learn together.