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

Posted by Aryan Monga
Aryan Monga
4,061 Points

Python conversion error!

The question is " You're doing great! Just one more task but it's a bigger one. Right now, we turn everything into a float. That's great so long as we're getting numbers or numbers as a string. We should handle cases where we get a non-number, though. Add a try block before where you turn your arguments into floats. Then add an except to catch the possible ValueError. Inside the except block, return None. If you're following the structure from the videos, add an else: for your final return of the added floats. "

I've been getting a ValueError saying that " could not convert a string into float" Please help me to edit the code! Let me know if there is any indentation error. Thnx;)

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

2 Answers

Stuart Wright
Stuart Wright
41,120 Points
Stuart Wright
Stuart Wright
41,120 Points

You have tried to add float(a) and float(b) together in the first line of your function. This will cause an error if a or b cannot be converted to float, and since this line is not inside your try/except construct, the program will just terminate. You need to move this line inside your try block.

It also looks like your return None statement is too far indented. It should have the same indentation as your return c line.

If you fix the two issues above I believe your code should pass.

Aryan Monga
Aryan Monga
4,061 Points

I still have some issues, could you write the correct code for me please? Thnx;)

Stuart Wright
Stuart Wright
41,120 Points
Stuart Wright
Stuart Wright
41,120 Points

Here's the full version of some code that passes the challenge. All I did was move one of the lines to a different place, and fixed some indentation:

def add(a, b):
    try:
        a=float(a)
        b=float(b)
        c= float(a) + float(b)
    except ValueError:
        return None
    else:
        return c
Aryan Monga
Aryan Monga
4,061 Points

Thnx a lot Stuart! ;)