说明：  这是我自己花了很多时间写的一个BP神经网络类，里面封装了网络初始化、训练、分类等功能。奉献出来与感兴趣的朋友分享，绝对可靠。
(that I spent a lot of time writing in a category BP neural network inside the network initialization package, training, classification capabilities. Dedication out with friends interested in sharing, absolutely reliable.)