Matlab 矩阵拼接和随机取列、取行

A = [1,2,3;
    4,5,6;
    7,8,9;
    10,11,12]

B = [0,1,2];

% ; 表示纵向拼接，B在A的下面。横向拼接为 ： 
C = [A; B]

s = size(A);

data_sum = s(1);   

% 取的比例
addPercentage = 0.5;

addNum = round(data_sum * addPercentage)

% 取列
selected = A(:,randperm(s(2),addNum))
% 取行
selected = A(randperm(s(2),addNum),:)