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README.md

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 # Machine-Learning-Notes(加载图片较慢，请耐心等待)
 周志华《机器学习》手推笔记~持续更新中
 
-*Last updated: 2019/09/20*
+## 手推笔记已经  35页 A4纸，可直接打印 ！！
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+*Last updated: 2019/09/24*
 
 ## 【计算机视觉联盟】回复【西瓜书手推笔记】即可获得百度云pdf下载链接
 
 
 #### Update log
 * 2019/09/20 * - 更新第二章，第三章
+* 2019/09/24 * - 更新第四章
 
 
 ## Table of Contents
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 ![image](https://github.com/Sophia-11/Machine-Learning-Notes/blob/master/ch3/%E6%89%AB%E6%8F%8F0022_%E5%89%AF%E6%9C%AC.jpg)
 ![image](https://github.com/Sophia-11/Machine-Learning-Notes/blob/master/ch3/%E6%89%AB%E6%8F%8F0023_%E5%89%AF%E6%9C%AC.jpg)
 
+## 第四章   决策树
+![image](https://github.com/Sophia-11/Machine-Learning-Notes/blob/master/ch4/%E6%89%AB%E6%8F%8F0024_%E5%89%AF%E6%9C%AC.jpg)
+![image](https://github.com/Sophia-11/Machine-Learning-Notes/blob/master/ch4/%E6%89%AB%E6%8F%8F0025_%E5%89%AF%E6%9C%AC.jpg)
+![image](https://github.com/Sophia-11/Machine-Learning-Notes/blob/master/ch4/%E6%89%AB%E6%8F%8F0026_%E5%89%AF%E6%9C%AC.jpg)
+![image](https://github.com/Sophia-11/Machine-Learning-Notes/blob/master/ch4/%E6%89%AB%E6%8F%8F0027_%E5%89%AF%E6%9C%AC.jpg)
+![image](https://github.com/Sophia-11/Machine-Learning-Notes/blob/master/ch4/%E6%89%AB%E6%8F%8F0028_%E5%89%AF%E6%9C%AC.jpg)
+![image](https://github.com/Sophia-11/Machine-Learning-Notes/blob/master/ch4/%E6%89%AB%E6%8F%8F0029_%E5%89%AF%E6%9C%AC.jpg)
+![image](https://github.com/Sophia-11/Machine-Learning-Notes/blob/master/ch4/%E6%89%AB%E6%8F%8F0030_%E5%89%AF%E6%9C%AC.jpg)
+![image](https://github.com/Sophia-11/Machine-Learning-Notes/blob/master/ch4/%E6%89%AB%E6%8F%8F0031_%E5%89%AF%E6%9C%AC.jpg)
+![image](https://github.com/Sophia-11/Machine-Learning-Notes/blob/master/ch4/%E6%89%AB%E6%8F%8F0032_%E5%89%AF%E6%9C%AC.jpg)
+![image](https://github.com/Sophia-11/Machine-Learning-Notes/blob/master/ch4/%E6%89%AB%E6%8F%8F0033_%E5%89%AF%E6%9C%AC.jpg)
+![image](https://github.com/Sophia-11/Machine-Learning-Notes/blob/master/ch4/%E6%89%AB%E6%8F%8F0034_%E5%89%AF%E6%9C%AC.jpg)
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