Here's a really simple, inefficient way:
M = rand(15,10)
for col = 1:size(M,2)
for iters = 1:size(M,1)
for row = 1:(size(M,1)-1)
if (M(row,col) > M(row+1,col))
temp = M(row,col);
M(row,col) = M(row+1,col);
M(row+1,col) = temp;
end
end
end
end
M
