How do I get the last element of a list?
some_list[-1]
is the shortest and most Pythonic.
In fact, you can do much more with this syntax. The some_list[-n]
syntax gets the nth-to-last element. So some_list[-1]
gets the last element, some_list[-2]
gets the second to last, etc, all the way down to some_list[-len(some_list)]
, which gives you the first element.
You can also set list elements in this way. For instance:
>>> some_list = [1, 2, 3]
>>> some_list[-1] = 5 # Set the last element
>>> some_list[-2] = 3 # Set the second to last element
>>> some_list
[1, 3, 5]
Note that getting a list item by index will raise an IndexError
if the expected item doesn't exist. This means that some_list[-1]
will raise an exception if some_list
is empty, because an empty list can't have a last element.
How to get the last value of an ArrayList
The following is part of the List
interface (which ArrayList implements):
E e = list.get(list.size() - 1);
E
is the element type. If the list is empty, get
throws an IndexOutOfBoundsException
. You can find the whole API documentation here.
How to get last items of a list in Python?
You can use negative integers with the slicing operator for that. Here's an example using the python CLI interpreter:
>>> a = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12]
>>> a
[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12]
>>> a[-9:]
[4, 5, 6, 7, 8, 9, 10, 11, 12]
the important line is a[-9:]
How to obtain the last index of a list?
len(list1)-1
is definitely the way to go, but if you absolutely need a list
that has a function that returns the last index, you could create a class that inherits from list
.
class MyList(list):
def last_index(self):
return len(self)-1
>>> l=MyList([1, 2, 33, 51])
>>> l.last_index()
3
Getting the last element of a list in dart
you can use last
property for read/write, inherited-getter:
last
is a returns the last element from the given list.
var lst = ["element1" , "element2" , "element3"];
lst.last // -> element3
or
lst[lst.length-1] //-> element3
How to get the last element of a slice?
For just reading the last element of a slice:
sl[len(sl)-1]
For removing it:
sl = sl[:len(sl)-1]
See this page about slice tricks
How can I find the last element in a List<>?
If you just want to access the last item in the list you can do
if (integerList.Count > 0)
{
// pre C#8.0 : var item = integerList[integerList.Count - 1];
// C#8.0 :
var item = integerList[^1];
}
to get the total number of items in the list you can use the Count
property
var itemCount = integerList.Count;
Selecting the last element of a list inside a pandas dataframe
df.column1 = df.column1.apply(lambda x: x[-1])
print(df)
Prints:
datetime. column1
0 2021-04-10 00:03 00. 30.7
1 2021-04-10 00:06 00. 20.7
2 2021-04-10 00:09 00. 10.7
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