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Alexander Davison
65,469 PointsI'd like to compare songs by their length (measured in whole seconds). Add the required methods for ==, <, >, <=, and >=
What's wrong with my code?
class Song:
def __init__(self, artist, title, length):
self.artist = artist
self.title = title
self.length = length
def __eq__(self, other):
return self.length == other.length
def __le__(self, other):
return self.length <= other.length
def __gr__(self, other):
return self.length > other.length
def __lt__(self, other):
return self.length < other.length
5 Answers
Christian Mangeng
15,970 PointsJust came upon this challenge, too, and thought I'd like to share my solution with you:
class Song:
def __init__(self, artist, title, length):
self.artist = artist
self.title = title
self.length = length
def __int__(self):
return int(self.length)
def __eq__(self, other):
return int(self) == other
def __gt__(self, other):
return int(self) > other
def __lt__(self, other):
return int(self) < other
def __ge__(self, other):
return int(self) >= other
def __le__(self, other):
return int(self) <= other
James J. McCombie
Python Web Development Techdegree Graduate 21,199 PointsI had a crack at this challenge, as Matt has already pointed out you had a method or two missing and your code did not implement comparing songs to ints, passed with:
class Song:
def __init__(self, artist, title, length):
self.artist = artist
self.title = title
self.length = length
def __int__(self):
return int(self.length)
def __eq__(self, other):
if isinstance(other, Song):
return self.length == other.length
elif isinstance(other, int):
return int(self) == other
else:
raise AttributeError
def __lt__(self, other):
if isinstance(other, Song):
return self.length < other.length
elif isinstance(other, int):
return int(self) < other
else:
raise AttributeError
def __le__(self, other):
if isinstance(other, Song):
return self.length < other.length or self.length == other.length
elif isinstance(other, int):
return int(self) <= other
else:
raise AttributeError
def __gt__(self, other):
if isinstance(other, Song):
return self.length > other.length
elif isinstance(other, int):
return int(self) > other
else:
raise AttributeError
def __ge__(self, other):
if isinstance(other, Song):
return self.length > other.length or self.length == other.length
elif isinstance(other, int):
return int(self) >= other
else:
raise AttributeError
Not entirely happy with the solution, but it passed. It may be an idea to add some type checking of sorts for the length property, may I also ask is this a new object orientated course you are following? as I really do not remember doing this the first time around
James
Kenneth Love
Treehouse Guest TeacherYou don't need that much code. What happens if you do, say, return int(self) > other? does that reduce a lot of work?
Tapiwanashe Taurayi
15,889 Pointsclass Song: def init(self, artist, title, length): self.artist = artist self.title = title self.length = length
def __int__(self):
return int(self.length)
def __eq__(self, other):
return int(self) == other
def __gt__(self, other):
return int(self) > other
def __lt__(self, other):
return int(self) < other
def __ge__(self, other):
return int(self) >= other
def __le__(self, other):
return int(self) <= other
Kenneth Love
Treehouse Guest TeacherIt's not __gr__, it's __ge__.
Matt Juergens
16,295 PointsHaven't got there in python yet, but you are missing one of those methods. Hope I helped.