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

Posted by wpnawzshaq
wpnawzshaq
861 Points

"try:" and built function

I don't know how to implement try and def function in it. I was worked as it wrote in instruction and it's wrong. I can't fix it because the attached chunk of code is not my logic it is just a results of following the instruction.

trial.py 
def add(a, b):
    try:
        except ValueError:
            return(none)
        else:
    return(float(a) + float(b))

1 Answer

Ryan S
Ryan S
27,276 Points
Ryan S
Ryan S
27,276 Points

Hi Juro,

When using a try: block, you need to try to do something in it. In this case, you are trying to see if your arguments "a" and "b" can be converted into a float. If they cannot (if they are non-numeric strings, for example), you will get an error. This is where the except ValueError: comes in, it will allow you to handle the error without breaking the code.

So the logic of the try/except blocks in this challenge would look something like this:

def add(num1, num2):
    try:
        #  try to convert num1 and num2 into floats
    except ValueError:
        #  If they cannot be converted and a ValueError is raised, handle it here.
    else:
        #  If the try block passed and no error was raised, return whatever you need to here.

Hope this helps.