说明：  BP神经网络算法的matlab代码,本程序根据训练好的网络文件预测新的数据文件，得到均方误差，并画出预测数据和原数据的对比
(BP neural network algorithm Matlab code, the procedures under the trained network file to predict new data file, the mean square error and draw the comparison of the predicted data and the original data)