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

Arun Patel
Arun Patel
1,180 Points
Posted by Arun Patel
Arun Patel
1,180 Points

What's wrong with the odds function?

I tried the odds function separately in python Shell with slicing [::2], for e.g for "arunpatel", I got ['a', 'u', 'p', 't', 'l']. Is this not correct?

slices.py 
def first_4(str1):
    str2 = list(str1)

    if len(str2) >= 4:
        list1 = str2[:4]
    else:
        return
    return list1


def first_and_last_4(str1):
    str2 = list(str1)
    if len(str2) >= 8:
        list1 = str2[:4] + str2[-4:]
    else:
        return
    return list1


def odds(str1):
    str2 = list(str1)
    list1 = str2[::2]
    return list1

2 Answers

Steven Parker
Steven Parker
216,032 Points
Steven Parker
Steven Parker
216,032 Points

You said "for "arunpatel", I got ['a', 'u', 'p', 't', 'l']. Is this not correct?", no that would be the items with even index numbers (0, 2, 4, ...etc). Remember that index numbers start at 0.

Arun Patel
Arun Patel
1,180 Points
Arun Patel
Arun Patel
1,180 Points

Thanks Steve, got it. It will be [1::2].