17: Functions in python

Try it:

Below you’ll see some example python code which asks the user to enter a number and keeps asking until they do:

Press Ctrl + Enter  to run the code.

Here’s how the code works:

Lines 3-10 define a function called enter_number. This tells python how to get the user to enter a number

Line 12 calls the function. This tells python to run the function code (make it actually happen)

Line 7 returns a value. This tells python to stop running the function and send a value back to line 12 where it is stored into the variable called value

Challenges:

Start by running the code.

1. Call enter_number again and save the return value into a variable called second_value
   

   Line 12 calls enter_number and saves the return value into a variable called value so you can copy and adapt that line

2. Change the function to return a float (real / decimal number) instead of an integer (whole number)
   

   Line 7 currently uses the int builtin function to convert the string you get from input into an integer. Use the float builtin function instead

3. Change the function so that it only returns if the user enters a value over 0
   

   You’ll need to use an if statement so that the function only returns if number is greater than 0

On the next page you’ll get some code with both syntax and logic errors

KPRIDE

KPRIDE stands for Keywords, Predict, Run, Investigate, Debug and Extend and it’s a way of helping you explore and understand python code. Click on the image below for a set of KPRIDE activities for this python skill.

Page 1: Intro

Page 2: The theory: learn what you need to know as fast as possible.

Page 3: Try it: try out and adapt some working python code snippets.

Page 4: Debug it: Learn how to find and fix common mistakes.

Page 5: Extend it: Choose a project idea to use your newfound python skills.