Function Basics

• It is possible to write a short Python script as a simple sequence of Python statements.
  • (That’s what we did during the last class)
• However, for all but the smallest programs, it is better to organize code into functions
• Functions are named chunks of code that can be used repeatedly
• Why?
  • Allows us to re-use code rather than re-typing it.
    • e.g., say math.sqrt rather than repeating the code to compute a square root every time you need one.
  • It’s easier to reason about smaller problems.
    • We can break a large, complex problem into many smaller, easier problems.
  • General coding principle: _D_on’t _R_epeat _Y_ourself: If you have multiple groups of identical code, then find a bug in one, you have to fix that same bug in all the copies.
• Write a basic function like say_hello
  • Notice that the contents of the function are determined by the indentation.
  • This is different from most languages!

• As with variables, the convention is to use snake_case with functions

• Work through tasks 1 and 2 from IC 2.