function r = my_reshape(a,m,n) % 存为 my_reshape.m
[m0,n0] = size(a);
mm = ceil(m/m0);
nn = ceil(n/n0);
r = repmat(a,mm,nn);
r = r(1:m,1:n);
%% 调用
a =[1 2 3;4 5 6];
m = 5; n = 5;
r = my_reshape(a,m,n)
r =
1 2 3 1 2
4 5 6 4 5
1 2 3 1 2
4 5 6 4 5
1 2 3 1 2