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

Posted by ellie adam
ellie adam
26,377 Points

Q1 of 3

Hi, How to solve this add function? Q. I need you to make a new function, add. add should take two arguments, add them together, and return the total.

def add(x, y):
    sum = x + y
    total = 'The sum of {} and {} is {}.'.format(x, y, sum)
    add(total)

thx

trial.py 
def add(x, y):
    sum = x + y
    total = 'The sum of {} and {} is {}.'.format(x, y, sum)
    add(total)

8 Answers

Ryan Ruscett
Ryan Ruscett
23,309 Points
Ryan Ruscett
Ryan Ruscett
23,309 Points

Hey,

You are on the right track, but let's break it down.

  1. Function called add.
  2. add takes 2 arguments
  3. return the two added together.

I totally understand why you created a sum that was the two values added together. That is fine too. You can definitely do that. But you also made a total which is a formatted string. Which you didn't have to do. Plus you only had two {} and three values. x, y and sum. So let's just scrap the total all together.

What you are actually doing is recursion. You created a recursive function. The last line add(total). Means you are calling add again, but passing it in total. Which is a string. Which is only 1 argument. The function takes 2 and since it's not a partial or an apply type function. Well, let's just scrap that too.

let's just focus on exactly what the question is asking. I think you may have over thought it.

def add(x, y):    # number 1 and 2
    return x + y   # number 3

Does that make sense? If not let me know and I can try to explain it differently.

Ary de Oliveira
Ary de Oliveira
28,298 Points

impressive

Ryan Ruscett
Ryan Ruscett
23,309 Points
Ryan Ruscett
Ryan Ruscett
23,309 Points

Hello,

There is no need for an else statement. The below code works just fine. The only thing I would use with a try and except would be a finally if I needed it. The code below works just fine. 

def add(x, y):
  try:
    a = float(x) 
    b = float(y)
  except ValueError
    return None
  return a + b
Patric Daniel Pförtner
Patric Daniel Pförtner
1,542 Points
Patric Daniel Pförtner
Patric Daniel Pförtner
1,542 Points

Hi Ellie,

You are very close to the answer, here is how I did it: 

def add(num1, num2):   
    return(num1 + num2)   # num 3

Why are you learning Python? Maybe we have the same aims! I am learning it to bring my Start UP www.wolf-gate.com to the next level. Thank´s to Kenneth Love it´s easily possible :)

akhter ali
akhter ali
15,778 Points
akhter ali
akhter ali
15,778 Points

You don't need to have "try/else" if you return None in one of the conditions. The following makes more sense to me.

def add(x, y)
    try:
        a = float(x)  
        b = float(y)
    except ValueError:
        return None
    return (a + b)
ellie adam
ellie adam
26,377 Points
ellie adam
ellie adam
26,377 Points

thanks, Need some help on Q3-3. It has error msg.

def add(x, y)
    try:
        a = float(x)  
        b = float(y)
    except ValueError:
        return None
     else:
        return True
naiara gonzalez
naiara gonzalez
16,778 Points
naiara gonzalez
naiara gonzalez
16,778 Points 
          def add(x, y):  # <-- changed from x+y
    try:
        a = float(x)
        b = float(y)
    except ValueError:
        return None
    else:
        return a + b
Silje Tellefsen
Silje Tellefsen
886 Points
Silje Tellefsen
Silje Tellefsen
886 Points 
def add(arg1, arg2):
    arg1 = float(arg1)
    arg2 = float(arg2)
    return(arg1 + arg2)
Baur Alzhanov
Baur Alzhanov
7,028 Points
Baur Alzhanov
Baur Alzhanov
7,028 Points

My version def add(x, y): return (x + y)