Python List Methods
Python List Methods
Python has a set of built-in methods that you can use on lists or arrays. Following are all of the methods of list objects:
| Methods | Explanation |
| append | The list.append() method adds an item to the end of the list. |
| extend | The list.extend() method extends the list by appending all the items from the iterable. |
| insert | The list.insert() method adds an element at the specified position |
| remove | The list.remove() method removes the first item with the specified value |
| pop | The list.pop() method removes the element at the specified position of the list. |
| Clear | The list.clear() method removes all the elements from the list |
| Index | The list.index() method returns the index of the first element with the given list value. |
| Count | The list.count() method returns the number of times x appears in the list. |
| Sort | This method sorts the items of the list |
| Reverse | This method reverses the elements of the list in place. |
| Copy | The list.copy() method returns a copy of the specified list. |
Example 1
# Python program explaining
# the list methods
# list.append() method
week_list = ["Monday", "Tuesday", "Wednesday","Thursday","Friday", "Saturday"]
print("List before calling append() method\n", week_list)
# appending sunday at the end of the list
week_list.append("Saturday")
print("List after calling append() method")
print(week_list)
#list.extend() method
str_list = ['The odd number', 'are:']
num_list = [1, 3, 5, 7, 9]
str_list.extend(num_list)
print ("The extended list:",str_list)
# list.remove() methods
num_list.remove(5)
num_list.remove(9)
print("After removing the 5,9 values:",num_list)
Output
List before calling append() method ['Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday'] List after calling append() method ['Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday', 'Saturday'] The extended list: ['The odd number', 'are:', 1, 3, 5, 7, 9] After removing the values: [1, 3, 7]
Example 2
# Python program explaining
# the list methods
# the list.pop() method
fruits = ['apple', 'banana', 'cherry']
print("List: ",fruits)
#removing the first element from the list
fruits.pop(1)
print("After removing the first element ")
print("List: ",fruits)
# list.index() method
# printing the index of 'cherry' in fruits list
print("The index value of string value 'cherry': ",fruits.index('cherry'))
# list.clear() method
fruits.clear()
print("After calling the clear() method..")
print("fruits list:",fruits)
Output
List: ['apple', 'banana', 'cherry'] After removing the first element List: ['apple', 'cherry'] The index value of string value 'cherry': 1 After calling the clear() method.. fruits list: []
Example 3
# Python program explaining
# the list methods
# passing the alphabets list
alphaList = ['b', 'a', 'e', 'd', 'c']
print("Actual list: ",alphaList)
# sort the alphabets list in the ascending order
alphaList.sort()
# priningt the list in a sorted order
print('Sorted list:',alphaList)
# list.reverse() method
# reversing the order of the alpha list
alphaList.reverse()
print('Reversed list:',alphaList)
# the list.copy() method
# copying the the old list
newList= alphaList.copy()
print("New List: ", newList)
Output
Actual list: ['b', 'a', 'e', 'd', 'c'] Sorted list: ['a', 'b', 'c', 'd', 'e'] Reversed list: ['e', 'd', 'c', 'b', 'a'] New List: ['e', 'd', 'c', 'b', 'a']