in Matlab I do this:
>> E = []; >> A = [1 2 3 4 5; 10 20 30 40 50]; >> E = [E ; A] E = 1 2 3 4 5 10 20 30 4
If you wanna do this just because you cannot concatenate an array with an initialized empty array in a loop, then just use a conditional statement, e.g.
if (i == 0): do the first assignment else: start your contactenate