BP神经网络学习方法与步骤，很详细，从基础开始-The BP neural network learning methods and steps, very detailed, starting the foundation

建立BP神经网络拟合曲面，实现激光焊接数据的预测(BP neural network mainly through 4 steps in the implementation of MATLAB, read file setting parameters, create a BP network, neural network training, neural network simulation. After the program, some basic parameters are set