直方图的平均值和标准差怎么算

简介：The first-generation Dragon Emperor had no chance of Jin Qianlei's little calculation, and he said to the second-generation Dragon Emperor sanctimoniously: Apprentice, I am not telling you as a master, you must be humble when walking in the human race! Otherwise, people will laugh at me because I don’t know how to teach my disciples! Although this emperor is wise, mighty, and has unparalleled supernatural powers,