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Please help! Problem with my Point object - itrema - Mar-05-2019
Hello everyone! I am having a problem with my code and after minutes of search, I landed here. I need your help.
Here is the problem: We want to create a Point object capable of handling the most basic vector operations; we want our Point object to handle addition and subtraction. For two points (x1,y1)+(x2,y2)=(x1+x2,y1+y2) and similarly for subtraction. Implement a method within Point that allows two Point objects to be added together using the + operator, and likewise for subtraction.
Here is my code:
class Point(object): def __init__(self, x, y): self.x = x self.y = y def __repr__(self): return "Point({0}, {1})".format(self.x, self.y) def __add__(self, other): a = self.x + other.x b = self.y + other.y return "Point({a}, {b})" def __sub__(a, b): c = self.x - other.x d = self.y - other.y return "Point({c}, {d})"And I've got type erreor.Can anyone help me?
By the way if you have an idea for multiplication, I'll be....
RE: Please help! Problem with my Point object - DeaD_EyE - Mar-05-2019
class Point(object): __slots__ = ['x', 'y'] def __init__(self, x, y): self.x = x self.y = y def __repr__(self): return "Point({0}, {1})".format(self.x, self.y) def __add__(self, other): x, y = self.x + other.x, self.y + other.y return self.__class__(x, y) def __sub__(self, other): x, y = self.x - other.x, self.y - other.y return self.__class__(x, y)- added __slots__ to save memory of the crated object from class
- method signature of sub was wrong
- A Point should be immutable. Doing an operation with two points, should return a new point.
Instead ofself.__class__, you can use also direct the namePoint.
The first one is good for inheritance.
For training, you could add other methods. For example a conversion to polar coordinates: https://en.wikipedia.org/wiki/Polar_coordinate_system#Converting_between_polar_and_Cartesian_coordinates
You can use a new class for this different representation or you do it inside of the
Point class, maybe as a property. RE: Please help! Problem with my Point object - itrema - Mar-05-2019
Thank you very much for your help. It worked