说明：  BP神经网络matlab实现，程序直接下载就可以运行，全部打包好。该程序主要用于分类iris数据，程序很完整，但不同于网络大部分程序，思路很好，值得学习，适用于初学BP神经网络的人。
(BP neural network matlab realize, you can run the program directly download all packed. The program is mainly used for classification iris data, the procedures are complete, but unlike most network programs, good ideas, it is worth learning for beginners BP neural network of people.)