curriculum/challenges/english/blocks/learn-special-methods-by-building-a-vector-space/65fd97f3c1b4c4839bdeb8d2.md
To compare two vectors, you are going to check that each component of the first vector is equal to the same component of the second vector.
After the if statement you created in the previous step, return True if each attribute of the current instance is equal to the same attribute of other and False otherwise.
The __eq__ method should return True if each attribute of the current instance is equal to the same attribute of other and False otherwise.
({ test: () => assert(runPython(`
v1 = R2Vector(x=2, y=3)
v2 = R2Vector(x=2, y=3)
v3 = R2Vector(x=0.5, y=1.25)
v4 = R3Vector(x=2, y=3, z=1.5)
v5 = R3Vector(x=2, y=3, z=1.5)
v6 = R3Vector(x=0.5, y=1.25, z=1.5)
v1 == v2 and not v1 == v3 and v4 == v5 and not v5 == v6
`)) })
class R2Vector:
def __init__(self, *, x, y):
self.x = x
self.y = y
def norm(self):
return sum(val**2 for val in vars(self).values())**0.5
def __str__(self):
return str(tuple(getattr(self, i) for i in vars(self)))
def __repr__(self):
arg_list = [f'{key}={val}' for key, val in vars(self).items()]
args = ', '.join(arg_list)
return f'{self.__class__.__name__}({args})'
def __add__(self, other):
if type(self) != type(other):
return NotImplemented
kwargs = {i: getattr(self, i) + getattr(other, i) for i in vars(self)}
return self.__class__(**kwargs)
def __sub__(self, other):
if type(self) != type(other):
return NotImplemented
kwargs = {i: getattr(self, i) - getattr(other, i) for i in vars(self)}
return self.__class__(**kwargs)
def __mul__(self, other):
if type(other) in (int, float):
kwargs = {i: getattr(self, i) * other for i in vars(self)}
return self.__class__(**kwargs)
elif type(self) == type(other):
args = [getattr(self, i) * getattr(other, i) for i in vars(self)]
return sum(args)
return NotImplemented
--fcc-editable-region--
def __eq__(self, other):
if type(self) != type(other):
return NotImplemented
--fcc-editable-region--
class R3Vector(R2Vector):
def __init__(self, *, x, y, z):
super().__init__(x=x, y=y)
self.z = z
v1 = R2Vector(x=2, y=3)
v2 = R2Vector(x=0.5, y=1.25)
print(f'v1 = {v1}')
print(f'v2 = {v2}')
v3 = v1 + v2
print(f'v1 + v2 = {v3}')
v4 = v1 - v2
print(f'v1 - v2 = {v4}')
v5 = v1 * v2
print(f'v1 * v2 = {v5}')