ax = NP.random.randint(10, 99, 20).reshape(5, 4)
fnx = lambda x: NP.sum(x) ** 2
new_row = NP.apply_along_axis(func1d=fnx, axis=0, arr=ax)
new_row = new_row.reshape(1, 4)
ax = NP.vstack((ax, new_row))
Building up an array in numpy/scipy by iteration in Python?