Python: Filter a list of integers using Lambda

Python Lambda: Exercise-5 with Solution

Write a Python program to filter a list of integers using Lambda.

Sample Solution:

Python Code :

# Create a list of integers named 'nums'
nums = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

# Display a message indicating that the following output will show the original list of integers
print("Original list of integers:")
print(nums)

# Display a message indicating that the following output will show even numbers from the list
print("\nEven numbers from the said list:")

# Use the 'filter()' function with a lambda function to filter even numbers from 'nums'
# Create a new list 'even_nums' containing only the even numbers from the original list
even_nums = list(filter(lambda x: x % 2 == 0, nums))
print(even_nums)

# Display a message indicating that the following output will show odd numbers from the list
print("\nOdd numbers from the said list:")

# Use the 'filter()' function with a lambda function to filter odd numbers from 'nums'
# Create a new list 'odd_nums' containing only the odd numbers from the original list
odd_nums = list(filter(lambda x: x % 2 != 0, nums))
print(odd_nums) 

Sample Output:

Original list of integers:
[1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

Even numbers from the said list:
[2, 4, 6, 8, 10]

Odd numbers from the said list:
[1, 3, 5, 7, 9]

Explanation:

In the exercise above -

• It initializes a list named 'nums' containing integers from 1 to 10.
• Prints the original list of integers ('nums') to the console.
• Filters even and odd numbers from the 'nums' list separately and prints them:
• It uses the "filter()" function with a lambda function to filter even numbers from the 'nums' list. The lambda function checks if the number is even (x % 2 == 0) and creates a new list called 'even_nums' containing only even numbers.
• It then prints the list of even numbers ('even_nums').
• Similarly, it uses the "filter()" function with a lambda function to filter odd numbers from the 'nums' list. The lambda function checks if the number is odd (x % 2 != 0) and creates a new list called 'odd_nums' containing only the odd numbers.
• It then prints the list of odd numbers ('odd_nums').

Test for a single number:

Python Code :

print((lambda x: (x % 2 and 'Odd number' or 'Even number'))(5))
print((lambda x: (x % 2 and 'Odd number' or 'Even number'))(8))

Sample Output:

Odd number
Even number

Python Code Editor:

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