I don't understand how the + Operator between v1 and v2 results in the calling of the function add in the code below.
self.a = a
self.b = b
def __str__(self):
return 'Vector (%d, %d)' % (self.a, self.b)
def __add__(self,other):
return Vector(self.a + other.a, self.b + other.b)
v1 = Vector(2,10)
v2 = Vector(5,-2)
print v1 + v2
Thanks
When the interpreter sees that you're trying to add something to a Vector object, it checks whether the object has a method called __add__(). If it does, the interpreter calls that method, passing both operands. The return value of the method is the result of the operation.
For each operator that can be overloaded there is a magic method that can be implemented to perform the operation.
This explanation is simplified in the sense that it is also possible for the right-hand operand (v2 in your example) to overload the operation. There are also special rules around in-place operator such as +=, and other complications.
