Function arguments in R Programming - Mini Project: Build & Apply

Function arguments

📖 Scenario: You are helping a small bakery calculate the total cost of different types of cakes ordered by customers. Each cake has a price and a quantity ordered.

🎯 Goal: Build a function that takes the price and quantity of a cake as arguments and returns the total cost. Then use this function to calculate the total cost for a specific order.

📋 What You'll Learn

Create a function called calculate_cost that takes two arguments: price and quantity.

Inside the function, multiply price by quantity and return the result.

Call the function with price = 15 and quantity = 3.

Print the result of the function call.

💡 Why This Matters

🌍 Real World

Calculating costs based on quantity and price is common in shops, restaurants, and online stores.

💼 Career

Understanding how to write functions with arguments is essential for automating calculations and processing data efficiently in many programming jobs.

1

Create the function skeleton

Write a function called calculate_cost that takes two arguments: price and quantity. For now, leave the function body empty.

R Programming

calculate_cost <- function(price, quantity) {
  # Your code here
}

Need a hint?

Use the function keyword to define a function with two arguments.

2

Add the calculation inside the function

Inside the calculate_cost function, multiply price by quantity and return the result using the return() function.

R Programming

calculate_cost <- function(price, quantity) {
  # Multiply price and quantity and return the result
  # Your code here
}

Need a hint?

Use return(price * quantity) to send back the total cost.

3

Call the function with specific values

Call the calculate_cost function with price = 15 and quantity = 3, and save the result in a variable called total.

R Programming

calculate_cost <- function(price, quantity) {
  return(price * quantity)
}

# Call the function and save the result
# Your code here

Need a hint?

Use total <- calculate_cost(15, 3) to call the function and store the result.

4

Print the total cost

Print the value of the variable total to show the total cost.

R Programming

calculate_cost <- function(price, quantity) {
  return(price * quantity)
}

total <- calculate_cost(15, 3)

# Print the total cost
# Your code here

Need a hint?

Use print(total) to display the total cost.