>> A=rand(3) a=mean(A,1) %按列平均 b=mean(A,2) %按行平均 c=mean(A(:)) %全部平均 A = 0.8134 0.8940 0.2876 0.7185 0.9507 0.9264 0.5008 0.4624 0.4963 a = 0.6776 0.7690 0.5701 b = 0.6650 0.8652 0.4865 c = 0.6722 >>