学习进度笔记26/学习总结6：降维 http://cookdata.cn/auditorium/course_room/10017/ 《The matrix cookbook》http://www.math.uwaterloo.ca/~hwolkowi/matrixcookbook.pdf http://cookdata.cn/note/view_static_note/91fef440f61ec0fa68c121b958fd6385/ http://cookdata.cn/course/course_introduction/1/ http://cookdata.cn/course/course_introduction/39/
