python numpy array append 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: append value to numpy array

x = np.random.randint(2, size=10)
x = np.append(x, 2)

Example 3: np array append

>>> import numpy as np
>>> np.append([[0, 1, 2], [3, 4, 5]],[[6, 7, 8]], axis=0)
array([[0, 1, 2],
       [3, 4, 5],
       [6, 7, 8]])

Example 4: how to add numpy arrays

added = a+b #elementwise
added_in_the_end = np.concatenate(a,b) #add at the end of the array
#if you want to add in multiple dimentions check the documentation of np.concatenate

Example 5: 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 6: 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)