add item to numpy array python code example

Example 1: numpy append number to array

import numpy as np
a = np.array([1, 2, 3])
newArray = np.append(a, [10, 11, 12])

Example 2: add item to numpy array python

>>> np.append([1, 2, 3], [[4, 5, 6], [7, 8, 9]])
array([1, 2, 3, ..., 7, 8, 9])

Example 3: add item to numpy array python

>>> np.append([[1, 2, 3], [4, 5, 6]], [[7, 8, 9]], axis=0)
array([[1, 2, 3],
       [4, 5, 6],
       [7, 8, 9]])
>>> np.append([[1, 2, 3], [4, 5, 6]], [7, 8, 9], axis=0)
Traceback (most recent call last):
    ...
ValueError: all the input arrays must have same number of dimensions, but
the array at index 0 has 2 dimension(s) and the array at index 1 has 1
dimension(s)

Example 4: numpy python add array

x1 = [1, 2]
x2 = [1, 2]
print(np.add(x1, x2))
# [2, 4]