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Start your free trialMark Chesney
11,747 Pointsredo of combo() after completing intermediate python track
I don't have a question... I just had two things to add, and felt it appropriate to post here:
1) My one-line completely Pythonic solution is as such:
def combo(iter1, iter2):
return [(iter1[i], iter2[i]) for i, _ in enumerate(iter1)]
2) I cracked up when I ran this code, and the message returned was:
** Bummer: Don't use zip()
! I know it exists but the point of this challenge is to solve the problem yourself. **
Anyway, just wanted to share a good laugh :D
# combo([1, 2, 3], 'abc')
# Output:
# [(1, 'a'), (2, 'b'), (3, 'c')]
def combo(iter1, iter2):
return list(zip(iter1, iter2))
Thank you very much!
Erik Burmeister
Python Web Development Techdegree Graduate 17,108 PointsMark, that is pretty funny. I was trying to solve the problem just now and I had heard in the past about zip() and thought it would work just fine here, however, I didn't get that message even though my code explicitly uses zip().
my code
def combo(*args): a = args[0] b = args[len(args)-1] x = list(zip(a,b)) return x
It marks it wrong though.
2 Answers
Mark Chesney
11,747 PointsHi Erik, thanks for responding. Weird, right? :)
I don't know what to tell you about your experience, unfortunately, because I've copied your code, and I get the don't use zip() message:
def combo(*args):
a = args[0]
b = args[len(args)-1]
x = list(zip(a,b))
return x
However, the good news is, if I run it in my local environment, it completely works! I stick this in afterwards:
if __name__ == '__main__':
test1 = combo([1, 2, 3], 'abc')
print(test1)
Erik Burmeister
Python Web Development Techdegree Graduate 17,108 PointsOh, wow! How strange. I actually reloaded the challenge and that time it did give me that error message. Glad it works!
I kinda know what that is but not sure what it means. Still learning. Haha.
Mark Chesney
11,747 PointsHi @rainmaker, I appreciate the question, and it's a great one. I'm not a highly experienced Pythonista. I've read joel grus' book data science from scratch: first principles with python. According to him:
# more pythonic:
for i, _ in enumerate(iterable):
pass
# less pythonic:
for i in range(len(iterable)):
pass
So I quickly jumped on stackoverflow just now and I see it may be up to debate: many others would perhaps agree with you here, claiming range(len(iterable))
is more readable.
One note I saw: for objects with no support for len()
, then range(len(iterable))
is prone to break. That same site also says:
Using xrange with len is quite a common use case, so yes, you can use it if you only need to access values by index.
Then another site mentions this:
range(len())
only works with countable, indexable objects.
enumerate
is faster when you want to repeatedly access the list/iterable items at their index. When you just want a list of indices, it is faster to to uselen()
andrange
(xrange
in Python 2.x)
End of the day, who knows? not me, for sure :)
rainmaker
14,690 Pointsrainmaker
14,690 Pointswhy did you use enumerate instead of range?