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User Defined Functions (Python)

Learning Objectives

• Define and call functions with parameters.
• Use default parameter values.
• Return computed results.

Example

def area_rectangle(length, width=1):
    return length * width

print(area_rectangle(5, 2))
print(area_rectangle(7))

Dry Run

• area_rectangle(5,2) -> 10
• area_rectangle(7) uses default width 1 -> 7

Common Mistakes

• Forgetting return when output is needed.
• Mismatch in number of arguments.

Practice

1. Write a function to find max of 3 numbers.
2. Return both sum and average from one function.