Important Functions of the Python List
We have mentioned some essential Python list functions along with their syntax and example:
1. Python sum() Method
Calculates the sum of all the elements of the List.
Syntax: sum(List)
Example:
List = [1, 2, 3, 4, 5]
print(sum(List))
Output
15
What happens if a numeric value is not used as a parameter?
The sum is calculated only for numeric values, else wise throws TypeError.
See example:
List = ['gfg', 'abc', 3]
print(sum(List))
Output:
Traceback (most recent call last):
File "", line 1, in
sum(List)
TypeError: unsupported operand type(s) for +: 'int' and 'str'
2. Python count() Method
Calculates the total occurrence of a given element of the List.
Syntax: List.count(element)
Example:
List = [1, 2, 3, 1, 2, 1, 2, 3, 2, 1]
print(List.count(1))
Output
4
3. Python len() Method
Calculates the total length of the List.
Syntax: len(list_name)
Example:
List = [1, 2, 3, 1, 2, 1, 2, 3, 2, 1]
print(len(List))
Output
10
4. Python index() Method
Returns the index of the first occurrence. The start and end indexes are not necessary parameters.
Syntax: List.index(element[,start[,end]])
Example:
List = [1, 2, 3, 1, 2, 1, 2, 3, 2, 1]
print(List.index(2))
Output
1
Another example:
In this example, we are using index() method which is one of the list functions in Python, searching the first occurrence of the element 2, starting from index 2 in the list.
List = [1, 2, 3, 1, 2, 1, 2, 3, 2, 1]
print(List.index(2, 2))
Output
4
5. Python min() Method
Calculates minimum of all the elements of List.
Syntax: min(iterable, *iterables[, key])
Example:
numbers = [5, 2, 8, 1, 9]
print(min(numbers))
Output
1
6. Python max() Method
Calculates the maximum of all the elements of the List.
Syntax: max(iterable, *iterables[, key])
Example:
numbers = [5, 2, 8, 1, 9]
print(max(numbers))
Output
9
7. Python sort() Method
Sort the given data structure (both tuple and list) in ascending order.
Key and reverse_flag are not necessary parameter and reverse_flag is set to False if nothing is passed through sorted().
Syntax: list.sort([key,[Reverse_flag]])
Example:
List = [2.3, 4.445, 3, 5.33, 1.054, 2.5]
#Reverse flag is set True
List.sort(reverse=True)
#List.sort().reverse(), reverses the sorted list
print(List)
Output
[5.33, 4.445, 3, 2.5, 2.3, 1.054]
8. Python reverse() Method
reverse() function reverses the order of list.
Syntax: list. reverse()
Example:
# creating a list
list = [1,2,3,4,5]
#reversing the list
list.reverse()
#printing the list
print(list)
Output
[5, 4, 3, 2, 1]
Python List methods
Python List Methods are the built-in methods in lists used to perform operations on Python lists/arrays.
Below, we’ve explained all the Python list methods you can use with Python lists, for example, append(), copy(), insert(), and more.