insert a new row to numpy array in especific position
>>> import numpy as np
>>> a = np.zeros((2, 2))
>>> a
array([[ 0., 0.],
[ 0., 0.]])
# In the following line 1 is the index before which to insert, 0 is the axis.
>>> np.insert(a, 1, np.array((1, 1)), 0)
array([[ 0., 0.],
[ 1., 1.],
[ 0., 0.]])
>>> np.insert(a, 1, np.array((1, 1)), 1)
array([[ 0., 1., 0.],
[ 0., 1., 0.]])