np.r_
import numpy as np
a = np.array([1, 2, 3])
b = np.array([4, 5, 6])
c = np.c_[a,b]
print(np.r_[a,b])
print(c)
print(np.c_[c,a])
[1 2 3 4 5 6]
[[1 4]
[2 5]
[3 6]]
[[1 4 1]
[2 5 2]
[3 6 3]]
Impossible Ibis