In this tutorial, we will learn about the Python List insert[] method with the help of examples.
The insert[] method inserts an element to the list at the specified index.
Example
# create a list of vowels
vowel = ['a', 'e', 'i', 'u']
# 'o' is inserted at index 3 [4th position]
vowel.insert[3, 'o']
print['List:', vowel]
# Output: List: ['a', 'e', 'i', 'o', 'u']Syntax of List insert[]
The syntax of the insert[] method is
list.insert[i, elem]
Here, elem is inserted to the list at the ith index.
All the elements after elem are shifted to the right.
insert[] Parameters
The insert[] method takes two parameters:
- index - the index where the element needs to be inserted
- element - this is the element to be inserted in the list
Notes:
- If index is 0, the element is inserted at the beginning of the list.
- If index is 3, the index of the inserted element will be 3 [4th element in the list].
Return Value from insert[]
The insert[] method doesn't return anything; returns None. It only updates the current list.
Example 1: Inserting an Element to the List
# create a list of prime numbers
prime_numbers = [2, 3, 5, 7]
# insert 11 at index 4
prime_numbers.insert[4, 11]
print['List:', prime_numbers]Output
List: [2, 3, 5, 7, 11]
Example 2: Inserting a Tuple [as an Element] to the List
mixed_list = [{1, 2}, [5, 6, 7]]
# number tuple
number_tuple = [3, 4]
# inserting a tuple to the list
mixed_list.insert[1, number_tuple]
print['Updated List:', mixed_list]Output
Updated List: [{1, 2}, [3, 4], [5, 6, 7]] Python List insert[] method inserts a given element at a given index in a list using Python.
Python List insert[] Syntax
Syntax: list_name.insert[index, element]
Parameters:
- index: the index at which the element has to be inserted.
- element: the element to be inserted in the list.
Returns: Does not return any value.
Python List insert[] Example
Python insert[] methods with string in Python.
Python3
lis = ['Geeks', 'Geeks']
lis.insert[1, "For"]
print[lis]
Output:
['Geeks', 'For', 'Geeks']
Example 1: Inserting an Element into the List
Here, we are inserting 10 at the 5th position[4th index] in a Python list.
Python3
list1 = [ 1, 2, 3, 4, 5, 6, 7 ]
list1.insert[4, 10]
print[list1]
Output:
[1, 2, 3, 4, 10, 5, 6, 7]
Example 2: Error of insert[] Method
Here, we are inserting 1 at the 10th position in a Python list, we will get an error, If we try to insert anything in a string because the string doesn’t have attribute insert[].
Python3
string = "1234567"
string.insert[10, 1]
print[string]
Output:
Traceback [most recent call last]:
File "/home/2fe54bd8723cd0ae89a17325da8b2eb5.py",
line 7, in
string.insert[10, 1]
AttributeError: 'str' object has no attribute 'insert'Example 3: Insertion in a List Before any Element
Here, we are inserting 13 at the 3rd position before 3 in a Python list.
Python3
list1 = [ 1, 2, 3, 4, 5, 6 ]
element = 13
beforeElement = 3
index = list1.index[beforeElement]
list1.insert[index, element]
print[list1]
Output:
[1, 2, 13, 3, 4, 5, 6]
Example 4: Inserting a Tuple into the List
Here we are inserting a tuple in a list using the insert[] function in Python.
Python3
list1 = [ 1, 2, 3, 4, 5, 6 ]
num_tuple = [4, 5, 6]
list1.insert[2, num_tuple]
print[list1]
Output:
[1, 2, [4, 5, 6], 3, 4, 5, 6]