In Python, use list methods clear(), pop(), and remove() to remove items (elements) from a list. It is also possible to delete items using del statement by specifying a position or range with an index or slice.

• Remove all items: clear()
• Remove an item by index and get its value: pop()
• Remove an item by value: remove()
• Remove items by index or slice: del
• Remove items that meet the condition: List comprehensions

See the following article for adding items to the list.

• Add an item to a list in Python (append, extend, insert)

Remove all items: clear()

You can remove all items from the list with clear().

l = list(range(10))
print(l)
# [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]

l.clear()
print(l)
# []

Remove an item by index and get its value: pop()

You can remove the item at the specified position and get its value with pop().

The index at the beginning is 0 (zero-based indexing).

l = list(range(10))
print(l)
# [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]

print(l.pop(0))
# 0

print(l)
# [1, 2, 3, 4, 5, 6, 7, 8, 9]

print(l.pop(3))
# 4

print(l)
# [1, 2, 3, 5, 6, 7, 8, 9]

You can use negative values to specify the position from the end. The index at the end is -1.

print(l.pop(-2))
# 8

print(l)
# [1, 2, 3, 5, 6, 7, 9]

If the argument is omitted, the last item is deleted.

print(l.pop())
# 9

print(l)
# [1, 2, 3, 5, 6, 7]

Specifying a nonexistent index raises an error.

# print(l.pop(100))
# IndexError: pop index out of range

Remove an item by value: remove()

You can remove the first item from the list where its value is equal to the specified value with remove().

l = ['Alice', 'Bob', 'Charlie', 'Bob', 'Dave']
print(l)
# ['Alice', 'Bob', 'Charlie', 'Bob', 'Dave']

l.remove('Alice')
print(l)
# ['Bob', 'Charlie', 'Bob', 'Dave']

If the list contains more than one matching the specified value, only the first one is deleted.

l.remove('Bob')
print(l)
# ['Charlie', 'Bob', 'Dave']

Specifying a nonexistent value raises an error.

# l.remove('xxx')
# ValueError: list.remove(x): x not in list

Remove items by index or slice: del

clear(), pop(), and remove() are methods of list. You can also remove elements from a list with del statements.

Specify the item to be deleted by index. The first index is 0, and the last index is -1.

l = list(range(10))
print(l)
# [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]

del l[0]
print(l)
# [1, 2, 3, 4, 5, 6, 7, 8, 9]

del l[-1]
print(l)
# [1, 2, 3, 4, 5, 6, 7, 8]

del l[6]
print(l)
# [1, 2, 3, 4, 5, 6, 8]

You can delete multiple items with slice.

l = list(range(10))
print(l)
# [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]

del l[2:5]
print(l)
# [0, 1, 5, 6, 7, 8, 9]

l = list(range(10))
del l[:3]
print(l)
# [3, 4, 5, 6, 7, 8, 9]

l = list(range(10))
del l[4:]
print(l)
# [0, 1, 2, 3]

l = list(range(10))
del l[-3:]
print(l)
# [0, 1, 2, 3, 4, 5, 6]

It is also possible to delete all items by specifying the entire range.

l = list(range(10))
del l[:]
print(l)
# []

You can also specify step as [start:stop:step].

l = list(range(10))
del l[2:8:2]
print(l)
# [0, 1, 3, 5, 7, 8, 9]

l = list(range(10))
del l[::3]
print(l)
# [1, 2, 4, 5, 7, 8]

See the following article for details on slices.

• How to slice a list, string, tuple in Python

Remove items that meet the condition: List comprehensions

Removing items that satisfy the condition is equivalent extracting items that do not satisfy the condition.

For this purpose, list comprehensions are used.

• List comprehensions in Python

An example of removing odd or even items (= keeping even or odd items) is as follows. % Is the remainder operator and i % 2 is the remainder of dividing i by 2.

In the list comprehension, a new list is generated. Unlike the list type method or del statement introduced so far, the original list is not changed.

l = list(range(10))
print(l)
# [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]

print([i for i in l if i % 2 == 0])
# [0, 2, 4, 6, 8]

print([i for i in l if i % 2 != 0])
# [1, 3, 5, 7, 9]

print(l)
# [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]

See the following article for details on extracting elements using list comprehensions.

• Extract, replace, convert elements of a list in Python

Other examples are as follows.

l = ['Alice', 'Bob', 'Charlie', 'Bob', 'David']
print(l)
# ['Alice', 'Bob', 'Charlie', 'Bob', 'David']

print([s for s in l if s != 'Bob'])
# ['Alice', 'Charlie', 'David']

print([s for s in l if s.endswith('e')])
# ['Alice', 'Charlie']

If you want to remove duplicate elements, use set().

• Remove / extract duplicate elements from list in Python

print(list(set(l)))
# ['David', 'Alice', 'Charlie', 'Bob']