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Python Python Collections (2016, retired 2019) Slices Slice Functions

Kimmo Ojala
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.a{fill-rule:evenodd;}techdegree
Kimmo Ojala
Python Web Development Techdegree Student 8,257 Points
Posted by Kimmo Ojala
.a{fill-rule:evenodd;}techdegree
Kimmo Ojala
Python Web Development Techdegree Student 8,257 Points

Reverse evens

Hi there,

I tested my code in workspace but in the challenge I get an error message saying that my code didn't return the right values. What am I doing wrong?

BR, Kimmo

slices.py 
def first_4(iterable):
    return iterable[0:4]

def first_and_last_4(iterable):
    return iterable[0:4] + iterable[-4:]

def odds(iterable):
    return iterable[1::2]

def reverse_evens(iterable):
    slice = iterable[::-1]
    return slice[::2]

2 Answers

eg3
eg3
2,681 Points

if you use your reverse_evens function on something like [1, 2, 3, 4, 5, 6] then it would return [6, 4, 2]. Hope you can find a right answer now?. You can perhaps try something like this:

def reverse_evens(iterable):
    odds = iterable[::2]
    slice = odds[::-1]
    print (slice)
Saeed Gohar
Saeed Gohar
3,066 Points
Saeed Gohar
Saeed Gohar
3,066 Points

Maybe look at this from another perspective if it helps. What I did to help me was look at it using an if statement Ex:

def reverse_evens(arg):
   if {arg is even}:
      return arg[start from -2 index and step back 2]
   else:
      return arg[start from -1 index and step back 2]

I hope this hint helps