Sub Programs (OCR GCSE Computer Science)

Creating a function

function squared(number)

squared = number^2

return squared

endfunction

def squared(number):

squared = number^2

return squared

Calling a function

SquNum = squared(4)

print(SquNum)

OR

print(SquNum(4))

SquNum = squared(4)

print(SquNum)

OR

print(SquNum(4))

Creating a procedure

procedure ageCheck(age)

if age > 18 then

print("You are old enough")

else

print("You are too young")

endif

endprocedure

def ageCheck(age):

if age > 18:

print("You are old enough")

else:

print("You are too young")

Calling a procedure

ageCheck(21)

ageCheck(21)

Functions

def area(length, width): # Function definition, length and width are parameters
  area = length * width # Calculate area
  return area # Return area

# Main program #1
length = int(input("Enter the length: ")) # Asks the user to enter the length
width = int(input("Enter the width: ")) # Asks the user to enter the width
print(area(length, width)) # Outputs the result of the function

# Main program #2
length = int(input("Enter the length: ")) # Asks the user to enter the length
width = int(input("Enter the width: ")) # Asks the user to enter the width
area = area(length, width) # Stores the result of the function in a variable
print("The area is " + str(area) + " cm^2") # Outputs the result of the function

Procedures

def main_menu(): # Function definition
  print("1. Addition") # Outputs the option
  print("2. Subtraction")
  print("3. Multiplication")
  print("4. Division")
  print("5. Exit")
  choice = int(input("Enter your choice: ")) # Asks the user to enter their choice
  if choice == 1: # If the user chooses 1
    addition() # Calls the addition function
  elif choice == 2:
    subtraction()
  elif choice == 3:
    multiplication()
  elif choice == 4:
    division()
  elif choice == 5:
    exit()

def addition(): # Function definition
  num1 = int(input("Enter the first number: ")) # Asks the user to enter the first number 
  num2 = int(input("Enter the second number: ")) # Asks the user to enter the second number
  print(num1 + num2) # Outputs the result of the addition

def subtraction():
  num1 = int(input("Enter the first number: "))
  num2 = int(input("Enter the second number: "))
  print(num1 - num2)

def multiplication():
  num1 = int(input("Enter the first number: "))
  num2 = int(input("Enter the second number: "))
  print(num1 * num2)

def division():
  num1 = int(input("Enter the first number: "))
  num2 = int(input("Enter the second number: "))
  print(num1 / num2)

# Main program
main_menu() # Calls the main_menu function

Global variables

globalVariable = 10 # Defines a global variable

def printValue():
    global globalVariable # Access the global variable inside a function
    print("The value into the variable is:", globalVariable)

printValue() # Call the function

Local variables

def printValue():
    localVariable = 10  # Defines a local variable inside the function
    print("The value of the local variable is:", localVariable)

printValue()  # Call the function