BP神经网络matlab程序，BP算法由数据流的前向计算（正向传播）和误差信号的反向传播两个过程构成。正向传播时，传播方向为输入层→隐层→输出层，每层神经元的状态只影响下一层神经元-BP neural network matlab program, BP algorithm the data stream forward calculation (forward propagation) and two back-propagation process error signal configu