Python Functions Exercise

A Python function is a block of code or a group of statements designed to perform a specific task. Functions are valuable for code reusability, allowing you to execute the same logic whenever needed without writing it multiple times.

This exercise on Python functions aims to help developers learn and practice defining functions, function calls, function arguments, inner functions, and built-in functions. Let us know in the comment section below if you have any alternative solutions. It will help other developers.

This exercise includes the following: –

• It contains Python function assignments, programs, questions, and challenges.
• Total 18 questions. The solution is provided for all questions and tested on Python 3.

Use Online Code Editor to solve exercise questions.

Exercise 1: Create a function in Python

Write a program to create a function that takes two arguments, name and age, and prints their values.

# demo is the function name
def demo(name, age):
    # print value
    print(name, age)

# call function
demo("Ben", 25)Code language: Python (python)

Exercise 2: Create a function with variable length of arguments

Write a program to create a function func1() that accepts a variable number of arguments and prints each of their values.

Note: Create this function so that it can receive any number of arguments, process them, and display the value of each individual argument.

Read: variable length of arguments in functions

Function call:

# call function with 3 arguments
func1(20, 40, 60)

# call function with 2 arguments
func1(80, 100)Code language: Python (python)

Expected Output:

Printing values
20
40
60

Printing values
80
100

def func1(*args):
  for arg in args:
    print(arg)

# Example calls to the function with different numbers of arguments
func1(10, 20)
func1("hello", 3.14, True)
func1(1, 2, 3, 4, 5)
func1() # Calling with no argumentsCode language: Python (python)

Exercise 3: Return multiple values from a function

Write a function calculation() that accepts two variables and calculates both their addition and subtraction. The function should then return both the sum and the difference in a single return statement.

Given:

def calculation(a, b):
    # Your Code

res = calculation(40, 10)
print(res)Code language: Python (python)

Expected Output

50, 30

Expected Output:

def calculation(a, b):
    addition = a + b
    subtraction = a - b
    # return multiple values separated by comma
    return addition, subtraction

# get result in tuple format
res = calculation(40, 10)
print(res)Code language: Python (python)

def calculation(a, b):
    return a + b, a - b

# get result in tuple format
# unpack tuple
add, sub = calculation(40, 10)
print(add, sub)Code language: Python (python)

Exercise 4: Create a function with a default argument

Write a program to create a function show_employee() with the following specifications:

• It should accept the employee’s name and salary.
• It should display both the name and salary.
• If the salary is not provided in the function call, it should default to 9000.

See: Default arguments in function

Given:

showEmployee("Ben", 12000)
showEmployee("Jessa")Code language: Python (python)

Expected output:

Name: Ben salary: 12000
Name: Jessa salary: 9000

# function with default argument
def show_employee(name, salary=9000):
    print("Name:", name, "salary:", salary)

show_employee("Ben", 12000)
show_employee("Jessa")Code language: Python (python)

Exercise 5: Create an inner function

Create a program with nested functions to perform an addition calculation as follows:

1. Define an outer function that accepts two parameters, a and b.
2. Inside this outer function, define an inner function that calculates the sum of a and b.
3. The outer function should then add 5 to this sum.
4. Finally, the outer function should return the resulting value.”

# outer function
def outer_fun(a, b):
    square = a ** 2

    # inner function
    def addition(a, b):
        return a + b

    # call inner function from outer function
    add = addition(a, b)
    # add 5 to the result
    return add + 5

result = outer_fun(5, 10)
print(result)Code language: Python (python)

Exercise 6: Create a recursive function

Write a program to create a recursive function that calculates the sum of numbers from 0 to 10.

A recursive function is a function that calls itself repeatedly.

Expected Output:

55

def addition(num):
    if num:
        # call same function by reducing number by 1
        return num + addition(num - 1)
    else:
        return 0

res = addition(10)
print(res)Code language: Python (python)

Exercise 7: Assign a different name to function and call it through the new name

Below is the function display_student(name, age). Assign a new name show_student(name, age) to it and call it using the new name.

Given:

def display_student(name, age):
    print(name, age)

display_student("Emma", 26)Code language: Python (python)

You should be able to call the same function using

show_student(name, age)Code language: Python (python)

def display_student(name, age):
    print(name, age)

# call using original name
display_student("Emma", 26)

# assign new name
showStudent = display_student
# call using new name
showStudent("Emma", 26)Code language: Python (python)

Exercise 8: Generate a Python list of all the even numbers between 4 to 30

Expected Output:

[4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28]

print(list(range(4, 30, 2)))Code language: Python (python)

Exercise 9: Find the largest item from list

Given:

x = [4, 6, 8, 24, 12, 2]Code language: Python (python)

Expected Output:

24

x = [4, 6, 8, 24, 12, 2]
print(max(x))Code language: Python (python)

Exercise 10: Call Function using both positional and keyword arguments

Define a function describe_pet(animal_type, pet_name) that prints a description of a pet. Call this function using both positional and keyword arguments.

def describe_pet(animal_type, pet_name):
  print(f"\nI have a {animal_type} named {pet_name}.")

# Calling the function using positional arguments
describe_pet('hamster', 'Harry')
describe_pet('dog', 'Lucy')

# Calling the function using keyword arguments
describe_pet(animal_type='cat', pet_name='Whiskers')
describe_pet(pet_name='Buddy', animal_type='goldfish')Code language: Python (python)

Exercise 11: Create a function with keyword arguments

The exercise requires you to create a function that can accept any number of keyword arguments. A keyword argument is where you specify the name of the argument along with its value (e.g., name="Alice", age=30). Inside the function, you need to access these arguments and print them in a key-value format.

Create a function print_info(**kwargs) that accepts keyword arguments and prints the key-value pairs. Call it with different keyword arguments

def print_info(**kwargs):
    if kwargs:  # Check if any keyword arguments were passed
        print("\n--- Information ---")
        for key, value in kwargs.items():
            print(f"{key}: {value}")
    else:
        print("\nNo information provided.")

# Example calls to the function
print_info(name="Alice", age=30, city="New York")
print_info(job="Engineer", salary=75000)
print_info(country="USA", state="California", zip_code="90210")
print_info()  # Call with no argumentsCode language: Python (python)

Exercise 12: Modifies global variable

Define a global variable global_var = 10. Write a function that modifies a global variable value.

global_var = 10

def modify_global_var():
    global global_var
    global_var = 20
    print("Inside function:", global_var)

modify_global_var()
print("Outside function:", global_var)Code language: Python (python)

Exercise 13: Write a recursive function to calculate the factorial

Write a recursive function to calculate the factorial of a non-negative integer.

def factorial_recursive(n):
    if n < 0:
        raise ValueError("Factorial is not defined for negative numbers")
    elif n == 0:
        return 1  # Base case: factorial of 0 is 1
    else:
        return n * factorial_recursive(n - 1)  # Recursive step

# Example usage:
number = 5
result = factorial_recursive(number)
print(f"The factorial of {number} is {result}")  
# Output: The factorial of 5 is 120
Code language: Python (python)

Exercise 14: Create a lambda function that squares a given number

A lambda function in Python is a small anonymous function defined using the lambda keyword. The syntax is lambda arguments: expression. The expression is evaluated and returned.

square = lambda x: x**2

# Example usage:
number = 5
squared_number = square(number)
print(f"The square of {number} is {squared_number}")Code language: Python (python)

Exercise 15: Use a lambda with the filter() function to get all even numbers from a list

Given:

numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]Code language: Python (python)

Expected Output:

The even numbers in the list are: [2, 4, 6, 8, 10]

numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
even_numbers = list(filter(lambda x: x % 2 == 0, numbers))
print(f"The even numbers in the list are: {even_numbers}")Code language: Python (python)

Exercise 16: Use a lambda with the map() function to double each element in a list

Given:

numbers = [1, 2, 3, 4, 5]Code language: Python (python)

Expected Output:

The doubled numbers are: [2, 4, 6, 8, 10]

numbers = [1, 2, 3, 4, 5]
doubled_numbers = list(map(lambda x: x * 2, numbers))
print(f"The doubled numbers are: {doubled_numbers}")Code language: Python (python)

Exercise 17: Use a lambda with the sorted() function to sort a list of tuples based on the second element

Given:

data = [('apple', 5), ('banana', 2), ('cherry', 8), ('date', 1)]Code language: Python (python)

Expected Output:

The sorted list of tuples based on the second element is: [('date', 1), ('banana', 2), ('apple', 5), ('cherry', 8)]

data = [('apple', 5), ('banana', 2), ('cherry', 8), ('date', 1)]
sorted_data = sorted(data, key=lambda item: item[1])
print(f"The sorted list of tuples based on the second element is: {sorted_data}")Code language: Python (python)

Exercise 18: Create Higher-Order Function

Write a function apply_operation(func, x, y) that takes a function func and two numbers x and y as arguments, and returns the result of calling func(x, y). Demonstrate its use with different functions (e.g., addition, subtraction).

The exercise requires you to create a higher-order function, which is a function that can take other functions as arguments.

def apply_operation(func, x, y):
  """
  Applies a given function to two numbers.

  Args:
    func: The function to apply (should take two arguments).
    x: The first number.
    y: The second number.

  Returns:
    The result of calling func(x, y).
  """
  return func(x, y)

# Demonstrate with addition using a regular function
def add(a, b):
  return a + b

result_add = apply_operation(add, 5, 3)
print(f"Result of addition: {result_add}")

# Demonstrate with subtraction using a lambda function
subtract = lambda a, b: a - b
result_subtract = apply_operation(subtract, 10, 4)
print(f"Result of subtraction: {result_subtract}")

# Demonstrate with multiplication using another lambda function
multiply = lambda a, b: a * b
result_multiply = apply_operation(multiply, 2, 6)
print(f"Result of multiplication: {result_multiply}")Code language: Python (python)