Lambda vs regular functions in Python - Hands-On Comparison

Lambda vs Regular Functions

📖 Scenario: Imagine you are organizing a small party and want to quickly calculate the cost of snacks based on quantity. You will use Python functions to do this calculation in two ways: with a regular function and with a lambda function.

🎯 Goal: Build two functions that calculate the total cost of snacks by multiplying the quantity by the price per snack. One function will be a regular function, and the other will be a lambda function. Then, compare their outputs.

📋 What You'll Learn

Create a regular function called calculate_cost that takes quantity and price_per_snack as parameters and returns the total cost.

Create a lambda function called calculate_cost_lambda that does the same calculation.

Use both functions to calculate the cost for 5 snacks priced at 2 each.

Print the results from both functions.

💡 Why This Matters

🌍 Real World

Functions help automate repetitive calculations like pricing items in a store or calculating bills quickly.

💼 Career

Understanding both regular and lambda functions is important for writing clean, efficient code in many programming jobs.

1

Create a regular function to calculate cost

Write a regular function called calculate_cost that takes two parameters: quantity and price_per_snack. It should return the product of these two parameters.

Python

# Your code here

Need a hint?

Use the def keyword to create a function. Multiply quantity by price_per_snack and return the result.

2

Create a lambda function to calculate cost

Create a lambda function called calculate_cost_lambda that takes quantity and price_per_snack as inputs and returns their product.

Python

def calculate_cost(quantity, price_per_snack):
    return quantity * price_per_snack

# Your code here

Need a hint?

Assign a lambda function to calculate_cost_lambda. The lambda should take two parameters and return their multiplication.

3

Calculate cost using both functions

Use the regular function calculate_cost and the lambda function calculate_cost_lambda to calculate the cost for 5 snacks priced at 2 each. Store the results in variables cost_regular and cost_lambda respectively.

Python

def calculate_cost(quantity, price_per_snack):
    return quantity * price_per_snack

calculate_cost_lambda = lambda quantity, price_per_snack: quantity * price_per_snack

# Your code here

Need a hint?

Call both functions with arguments 5 and 2, and save their results in cost_regular and cost_lambda.

4

Print the results

Print the values of cost_regular and cost_lambda on separate lines.

Python

def calculate_cost(quantity, price_per_snack):
    return quantity * price_per_snack

calculate_cost_lambda = lambda quantity, price_per_snack: quantity * price_per_snack

cost_regular = calculate_cost(5, 2)
cost_lambda = calculate_cost_lambda(5, 2)

# Your code here

Need a hint?

Use two print statements to show the values of cost_regular and cost_lambda.