log: 公式: 求导: 求导: LR: https://www.imooc.com/article/46843 ftrl优化: https://www.cnblogs.com/massquantity/p/12693314.html weighted LR: https://www.cnblogs.com/hellojamest/p/11871108.html FM: http://castellanzhang.github.io/2016/10/16/fm_ftrl_softmax/#more https://cloud.tencent.com/developer/article/1772608