1.1.5 Functions and procedures

• Functions and procedures are blocks of code designed to perform specific tasks
• Functions always return a value after execution.
• Procedures are also known as subroutines or void functions
• Procedures do not return a value.
• What is the primary use case of a procedure?

  Executes a task without returning a result
• The main difference between functions and procedures lies in their return value
• Procedures do not return a value.
• What is the role of a return statement in a function?

  Sends a value back
• The name of a function or procedure is a unique identifier
• Only functions require a return statement.
• What is an alternative term for a procedure?

  Void function
• Procedures return a value after execution.

  False
• A function like `add(x, y)` returns the sum
• What is the purpose of a procedure like `print_message(text)`?

  Prints a message
• What is the primary use case of a function?

  Calculates and returns a result
• A function can add two numbers and return their sum.
• A procedure might print a message
• Why is the distinction between functions and procedures important?

  Structured and reusable code
• Arrange the components of a function or procedure structure.

  1️⃣ Name

  2️⃣ Parameters

  3️⃣ Body

  4️⃣ Return statement (if applicable)
• The return statement is used in functions
• What does the following function calculate: \text{def calculate_{a}rea(width, height):} \\ \hspace{1em} \text{area} = \text{width} * \text{height} \\ \hspace{1em} \text{return area}</latex>?

  Area of a rectangle
• A procedure, also known as a void function, does not return a value.
• How do you call a function or procedure in code?

  Use its name with parameters
• To define a function or procedure, use the keyword def
• What keyword is used to return a value from a function?

  return
• Procedures do not return a value but can execute tasks.
• Comparing function and procedure calls, a function returns a value
• A procedure call does not usually assign its result to a variable.
• What keyword is used to define functions and procedures in code?

  def
• Functions return a value using the return statement.
• Procedures do not return a value.
• Match the feature with the type of call:

  Returns a value ↔️ Function Call

  No return value ↔️ Procedure Call
• What is an example of a function that adds two numbers?

  $def add(x, y): return x +$$y$
• Procedures often use the print statement to display output.
• Procedures always return a value.

  False
• What is the purpose of a function in programming?

  Return a calculated value
• Procedures are also known as void functions or subroutines.
• Steps to implement functions and procedures in code

  1️⃣ Define the function or procedure using `def`

  2️⃣ Specify parameters in parentheses

  3️⃣ Write the code block

  4️⃣ Use `return` for functions

  5️⃣ Call the function or procedure
• What is the output of calling `add(5, 3)` in the example provided?

  8
• Procedures can be assigned to variables.

  False