Arguments and Return Values

Passing Arguments

def add(a, b):        # a, b are FORMAL parameters (placeholders)
    return a + b

result = add(5, 3)     # 5, 3 are ACTUAL arguments (real values passed)
print(result)            # 8

Formal vs Actual Arguments

def multiply(x, y):    # x, y = formal parameters
    return x * y

print(multiply(4, 5))    # 4, 5 = actual arguments -> 20

return Statement

return sends a value back to the caller and ends function execution immediately.

def check_even(n):
    if n % 2 == 0:
        return True
    return False

print(check_even(10))   # True
print(check_even(7))    # False

Returning Multiple Values

Python functions can return multiple values as a tuple:

def min_max(numbers):
    return min(numbers), max(numbers)

low, high = min_max([4, 9, 1, 7])
print(low, high)   # 1 9

Function with no arguments and no return

def welcome():
    print("Welcome!")

welcome()   # Welcome!

Positional Arguments (order matters)

def student_info(name, age, course):
    print(name, age, course)

student_info("Riya", 21, "BCA")   # matched by POSITION

Passing a function's return value into another function

def square(n):
    return n * n

def cube(n):
    return n * n * n

print(square(3) + cube(2))   # 9 + 8 = 17