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Python Object-Oriented Python Advanced Objects Multiplication

Dmitriy Ignatiev
PLUS
Dmitriy Ignatiev
Courses Plus Student 6,236 Points
Posted by Dmitriy Ignatiev
Dmitriy Ignatiev
Courses Plus Student 6,236 Points

__mul__

What's wrong with my code

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):
        return self.value * other

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

2 Answers

Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 68,441 Points
Chris Freeman
Chris Freeman
Treehouse Moderator 68,441 Points

The __mul__ should return the correct value type depending if the string represents a float or an int. Check if string contains a period indicating a float. Convert value to float or int accordingly.

Also, __rmul__ will call __mul__, use "self" instead of "self.value". And watch the indentation.

Gilbert Craig
Gilbert Craig
2,102 Points
Gilbert Craig
Gilbert Craig
2,102 Points

I applied your suggestion but am still getting the same error

    def _mul__(self, other):
        if '.' in self.value:
            return float(self) * other
        return int(self) * other

    def __rmul__(self, other):
        return self * other
Chris Freeman
Chris Freeman
Treehouse Moderator 68,441 Points
Chris Freeman
Chris Freeman
Treehouse Moderator 68,441 Points

So close Gilbert! You're missing an underscore before _mul__

Dmitry Bruhanov
Dmitry Bruhanov
8,513 Points
Dmitry Bruhanov
Dmitry Bruhanov
8,513 Points

Dima, Hi!

The answer is in the question))

for the mul function: Copy the body of add and replace the '+' sign with the '*' sign.

Do the same with radd and rmul and you're done))