Python List Operations
This document describes common Python list operations, including adding and deleting elements, and concatenating lists. The github repo is this.
1. Adding Elements to a List
You can add elements to a Python list using the append() method to add an element to the end of the list, the insert() method to insert an element at a specific position, or the extend() method to add elements from another list.
Adding to the End of a List
To add an element to the end of a list, use the append() method:
my_list = [1, 2, 3]
my_list.append(4)
print(my_list) # Output: [1, 2, 3, 4]Inserting at a Specific Position
To insert an element at a specific position in a list, use the insert() method:
my_list = [1, 2, 3]
my_list.insert(1, 4)
print(my_list) # Output: [1, 4, 2, 3]This code inserts the value 4 at position 1 in the list my_list.
Adding Elements from Another List
To add elements from another list to the end of a list, use the extend() method:
my_list = [1, 2, 3]
other_list = [4, 5, 6]
my_list.extend(other_list)
print(my_list) # Output: [1, 2, 3, 4, 5, 6]2. Deleting Elements from a List
You can delete elements from a Python list using the pop() method to remove an element at a specific position, the remove() method to remove the first occurrence of a specific value, or the del statement to remove a slice of the list.
Removing an Element at a Specific Position
To remove an element at a specific position in a list, use the pop() method:
my_list = [1, 2, 3, 4]
my_list.pop(1)
print(my_list) # Output: [1, 3, 4]This code removes the element at position 1 in the list my_list.
Removing the First Occurrence of a Value
To remove the first occurrence of a specific value in a list, use the remove() method:
my_list = [1, 2, 3, 2]
my_list.remove(2)
print(my_list) # Output: [1, 3, 2]This code removes the first occurrence of the value 2 in the list my_list.
Removing a Slice of a List
To remove a slice of a list, use the del statement:
my_list = [1, 2, 3, 4, 5]
del my_list[1:3]
print(my_list) # Output: [1, 4, 5]This code removes the elements from position 1 to 3 (exclusive) in the list my_list.
3. Concatenating Lists
You can concatenate two or more Python lists using the + operator or the extend() method:
my_list = [1, 2, 3]
other_list = [4, 5, 6]
concatenated_list = my_list + other_list
print(concatenated_list) # Output: [1, 2,3,4,5,6]
