Can anybody help me?

Question

Can anybody explain me this code(cannot understand matmul function), please:

class l(list):
def __matmul__(self,other):
new=l()
for k in range(len(other)):
new.append(self[k]+other[k])
return new
i1=l((1,2,3,4,5))
i2=l((9,8,7,6,5))
i3=i1@i2
print(sum(i3))

Answer 1

I think you are struggling of __matmul__ and the @-operator. Both are related to matrix multiplication.

Find more information at:

https://stackoverflow.com/questions/27385633/what-is-the-symbol-for-in-JUMP_LINK__&&__python__&&__JUMP_LINK

Answer 2

Normally the @ operator is used by numpy for matrix multiplication.
In your sample code, the meaning of this operator is overridden by the magic method __matmul__
Your class l is subclass of list, with the additional capability that two l objects can be combined with this operator. As it is implemented, it adds the values element-wise to create a new l object, so the result of i1@i2 will be [10, 10, 10, 10, 10]

Answer 3

Thank you Tibor Santa