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Python Object-Oriented Python Advanced Objects Multiplication

I need to you add __mul__ to NumString so we can multiply our number string by a number. Go ahead and add __rmul__, too.

Need help tell me what I am doing wrong. Thanks.

numstring.py
class NumString:
    def __init__(self, value):
        self.value = str(value)

    def __str__(self):
         return self.value

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

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

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

    def __radd__(self, other):
        return self + other

    def __iadd__(self, other):
        self.value = self + other
        return self.value

    def __mul__(self, other):
        self.value = self * other
        return self.value

    def __rmul__(self, other):
         return self * other

2 Answers

Jason Anders
MOD
Jason Anders
Treehouse Moderator 145,860 Points

Hi Karen,

Your rmul is correct.

Have a look at the__mul__ and compare to how the__add__ is implemented. You need to check you see you you're working with an Integer or a Float. If you follow the structure of the __add__ method, I'm sure you'll get it.

Nice work! :) :dizzy:

Adem Gun
Adem Gun
1,511 Points

Why do we need to add : if '.' in self.value:

to mul but not to rmul?

Antonio Falcetta
Antonio Falcetta
14,192 Points
   def __mul__(self, other):
        if '.' in self.value:
            return float(self) * other
        return int(self) * other

    def __rmul__(self, other):
        return self * other