基于协同过滤的推荐系统案列

https://nbviewer.jupyter.org/github/China-LuoYaxiong/ipynb/blob/master/%E5%9F%BA%E4%BA%8E%E5%8D%8F%E5%90%8C%E8%BF%87%E6%BB%A4%E7%9A%84%E6%8E%A8%E8%8D%90%E7%B3%BB%E7%BB%9F%E6%A1%88%E4%BE%8B.ipynb