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Python Object-Oriented Python Advanced Objects Math

Math chapter

I followed kenneth coding, but when I use the add method with NumString(2.2) + 2 I receive a Type Error: float() argument must be a string or a number, not 'NumString'. I don't understand where the mistake is. Here my code:

class NumString: def init(self, value): self.value = str(value)

def __str__(self):
    return self.value

def __int__(self):
    return int(self.value)

def __foat__(self):
    return float(self.value)

def __add__(self, other):
    if '.' in self.value:
        return float(self) + other
    return int(self) + other

3 Answers

It looks like your init function is off. You don't seem to have init(). Instead you have init() without the dunders. Change that and your code should work.

I see, you misspelled float in foat. You miss the l.

Ignazio Calo
Ignazio Calo
Courses Plus Student 1,819 Points

with this code NumString(2.2) you're passing a number and not a string as parameter. NumString("2.2") should fix the problem

I agree with you, but then I don't understand why kenneth get the result using the same code I am using and using the code: NumString(2.2) + 2