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Python Python Basics (2015) Logic in Python Try and Except

Gregory Heard
Gregory Heard
1,975 Points
Posted by Gregory Heard
Gregory Heard
1,975 Points

How do i get this function to pass to the end return?

I am just confused about how i am getting integers to pass into my try block. I can get try blocks working easily when i can define the parameters. Also returning None on th except block... what does it do?

Thanks in advance!

trial.py 
def add (num1, num2):
  try:
    (num1 + num2)
  except ValueError:
    return None
  num1 = float(num1)
  num2 = float(num2)
  else
    return (num1 + num2)

2 Answers

Carlos Federico Puebla Larregle
Carlos Federico Puebla Larregle
21,073 Points
Carlos Federico Puebla Larregle
Carlos Federico Puebla Larregle
21,073 Points

Actually you have to "try" to float them, if they can't be "parse" to float you return "None" in the "except" block. If the "except" block is never reach you return the addition of the two numbers.

def add(num1, num2):
    try:
        num1 = float(num1)
        num2 = float(num2)
    except ValueError:
        return None
    return num1 + num2

I hope that helps a little bit

Gregory Heard
Gregory Heard
1,975 Points
Gregory Heard
Gregory Heard
1,975 Points

Oh i see! So you use the act of trying to float the integers as your check. Thank you very much!