Numpy: Append items to array

# Import library
import numpy as np

# Create 1-D array
x = np.array([1,2,3]) 

# Append
y = np.append(x, [999]) # Default axis=None

# Output
print('Original array:\n', x, '\n', 'Shape:',x.shape,'\n')
print('After append:\n', y, '\n', 'Shape:',y.shape,'\n')

Original array:
 [1 2 3] 
 Shape: (3,) 

After append:
 [  1   2   3 999] 
 Shape: (4,) 

# Import library
import numpy as np

# Create an array
x = np.array([[1,2],
             [10,20]])

# Append
y = np.append(x, [[888,999],[666,777]], axis=1)

# Output
print('Original array:\n', x, '\n', 'Shape:',x.shape,'\n')
print('After append:\n', y, '\n', 'Shape:',y.shape,'\n')

Original array:
 [[ 1  2]
 [10 20]] 
 Shape: (2, 2) 

After append:
 [[  1   2 888 999]
 [ 10  20 666 777]] 
 Shape: (2, 4)

# Import library
import numpy as np

# Create an array
x = np.array([[1,2],
             [10,20]])

# Append
y = np.append(x, [[888,999],[666,777]], axis=0)

# Output
print('Original array:\n', x, '\n', 'Shape:',x.shape,'\n')
print('After append:\n', y, '\n', 'Shape:',y.shape,'\n')

Original array:
 [[ 1  2]
 [10 20]] 
 Shape: (2, 2) 

After append:
 [[  1   2]
 [ 10  20]
 [888 999]
 [666 777]] 
 Shape: (4, 2)