How to slice a list from an element n to the end in python?

user_60893 0
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I'm having some trouble figuring out how to slice python lists, it is illustrated as follows:

>>> test = range(10)
>>> test
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
>>> test[3:-1]
[3, 4, 5, 6, 7, 8]
>>> test[3:0]
[]
>>> test[3:1]
[]
>>> test
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]

To my understanding, python slice means lst[start:end], and including start, excluding end. So how would i go about finding the "rest" of a list starting from an element n?

Thanks a lot for all your help!

sequence slice list python
7 Answers

You can leave one end of the slice open by not specifying the value.

test[3:] = [3, 4, 5, 6, 7, 8, 9]
test[:3] = [0, 1, 2]
Angela_719300

If you're using a variable as the range endpoint, you can use None.

 start = 4
 end = None
 test[start:end]
recursive_447430

Simply omit the end.

test[n:]
user_749110

You can also use the None keyword for the end parameter when slicing. This would also return the elements till the end of the list (or any sequence such as tuple, string, etc.)

# for list
In [20]: list_ = list(range(10))    
In [21]: list_[3:None]
Out[21]: [3, 4, 5, 6, 7, 8, 9]

# for string
In [22]: string = 'mario'
In [23]: string[2:None]
Out[23]: 'rio'

# for tuple
In [24]: tuple_ = ('Rose', 'red', 'orange', 'pink', 23, [23, 'number'], 12.0)
In [25]: tuple_[3:None]
Out[25]: ('pink', 23, [23, 'number'], 12.0)
user_29560660

What you are looking for is to use something like:

inputs = "ababbbaAab"
for i in range(n):
    print(i, inputs[:i] + inputs[i:i+1])

The output:

0 a
1 ab
2 aba
3 abab
4 ababb
5 ababbb
6 ababbba
7 ababbbaA
8 ababbbaAa
9 ababbbaAab

See that if i == 0

then inputs[:i] == [] and inputs[i:i+1] == a

and if i == len(inputs) - 1

then inputs[:i] == [ababbbaAa] and inputs[i:i+1] == b

user_14645710
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