NumPy: Append values to the end of an array

Last update on March 24 2025 13:37:24 (UTC/GMT +8 hours)

Append Values to Array

Write a NumPy program to append values to the end of an array.

Sample Solution:-

Python Code:

# Importing the NumPy library with an alias 'np'
import numpy as np

# Creating a Python list
x = [10, 20, 30]

# Printing a message indicating the original array
print("Original array:")

# Printing the original array
print(x)

# Appending values to the end of the array using np.append() and assigning the result back to 'x'
x = np.append(x, [[40, 50, 60], [70, 80, 90]])

# Printing a message indicating the array after appending values
print("After append values to the end of the array:")

# Printing the array after appending values
print(x)

Sample Output:

Original array:                                                         
[10, 20, 30]                                                            
After append values to the end of the array:                            
[10 20 30 40 50 60 70 80 90]

Explanation:

In the above code -

x = [10, 20, 30]: Defines a list called ‘x’ with three integer elements.

x = np.append(x, [[40, 50, 60], [70, 80, 90]]): The np.append() function is used to append two lists of three elements each to the original list ‘x’. The resulting object is converted into a NumPy array and stored back into ‘x’.

For more Practice: Solve these Related Problems:

• Append a single scalar value to a one-dimensional array and verify the updated length.
• Use np.append to concatenate two arrays and then check that the combined array preserves the original order.
• Append multiple values to an array and ensure the array’s dtype remains consistent throughout.
• Create a function that appends new values to an array only if they are not already present.

Python-Numpy Code Editor: