Related Articles

Related Articles

Python list | insert()
  • Difficulty Level : Easy
  • Last Updated : 18 Sep, 2018

insert() is an inbuilt function in Python that inserts a given element at a given index in a list.

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 :

This method does not return any value but
it inserts the given element at the given index.

Error :



If anything other then a list is used with 
insert(), then it returns an AttributeError.

Note : If given index >= length(list) is given, then it inserts at the end of the list.

Code #1 :

filter_none

edit
close

play_arrow

link
brightness_4
code

# Python3 program for use  
# of insert() method 
  
list1 = [ 1, 2, 3, 4, 5, 6, 7
  
# insert 10 at 4th index 
list1.insert(4, 10
print(list1) 
  
list2 = ['a', 'b', 'c', 'd', 'e'
  
# insert z at the front of the list
list2.insert(0, 'z')
print(list2) 

chevron_right


Output :

[1, 2, 3, 4, 10, 5, 6, 7]
['z', 'a', 'b', 'c', 'd', 'e']

 
Code #2 :

filter_none

edit
close

play_arrow

link
brightness_4
code

# Python3 program for error  
# of insert() method 
  
# attribute error 
string = "1234567"
  
string.insert(10, 1)
print(string) 

chevron_right


Output :

Traceback (most recent call last):
  File "/home/2fe54bd8723cd0ae89a17325da8b2eb5.py", line 7, in 
    string.insert(10, 1)
AttributeError: 'str' object has no attribute 'insert'

 

Practical Application :
Insertion in a list before any element :

Code #3 :

filter_none

edit
close

play_arrow

link
brightness_4
code

# Python3 program for Insertion in a list  
# before any element using insert() method 
  
list1 = [ 1, 2, 3, 4, 5, 6 ]
  
# Element to be inserted 
element = 13 
  
# Element to be inserted before 3
beforeElement = 3 
  
# Find index
index = list1.index(beforeElement) 
  
# Insert element at beforeElement 
list1.insert(index, element) 
print(list1)

chevron_right


Output :

[1, 2, 13, 3, 4, 5, 6]

Attention geek! Strengthen your foundations with the Python Programming Foundation Course and learn the basics.

To begin with, your interview preparations Enhance your Data Structures concepts with the Python DS Course.




My Personal Notes arrow_drop_up
Recommended Articles
Page :