中文说明：BP神经网络的训练函数,创建一个模式识别网络（两层BP网络）对数据进行预处理,把训练数据分成三部分，训练网络、验证网络、测试网络，训练函数，使用均方误差来评估网络
English Description：
BP neural network training function to create a pattern recognition network (two layer BP network) to preprocess the data, the training data is divided into three parts, training platform, verify the network, test the network, training function using mean squared error to evaluate the network