How to use one object attribute automatically whenever the object is called

Question

Is there a way to do arithmetic on python class objects, and all the operations will be applied to one attribute automatically. For example:

>>> x = Struct(__data__ = [100,100])
>>> y = Struct(__data__ = [200,200])
>>> x + y
Struct(__data__ = [300,300])
>>> np.array(x) + np.array(y)
np.array(Struct(__data__ = [300,300]))
>>> x += y
x ==> Struct(__data__ = [300,300])
>>> x[1:] = 50
x ==> Struct(__data__ = [300,50])

I want it to perform like a normal number/array, and all the operations apply to .__data__ automatically.

Does this answer your question? [Overloading Addition, Subtraction, and Multiplication Operators](https://stackoverflow.com/questions/20507745/overloading-addition-subtraction-and-multiplication-operators) — Josh Clark, Apr 17 '20 at 16:13
Thanks for the useful link, and I am currently doing this, just feel there should be an easier way to handle such a common problem. — small, Apr 17 '20 at 19:23

score 0 · Accepted Answer · answered Apr 17 '20 at 16:19

0

Yes it's possible. You need to define you dunder or magic methods__add__, __mul__, __eq__ etc for your class.

answered Apr 17 '20 at 16:19

NomadMonad

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Thank you, this is very helpful. – small Apr 17 '20 at 19:25

How to use one object attribute automatically whenever the object is called

1 Answers1