49

In Python, how can I remove an object from a list of objects? Like this:

x = object()
y = object()
array = [x, y]
# Remove x

I've tried array.remove() but it only works with a value, not a specific location in the array. I need to be able to delete the object by addressing its position (remove array[0]).

mkrieger1
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user1120190
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  • The code comment in your post _is_ the answer: it's just `array.remove(x)`, you don't need its position at all. After all, how would you even know `x` is in position 0 without knowing `x`? – Mike 'Pomax' Kamermans Feb 11 '23 at 22:21

8 Answers8

87

There are various ways to delete an object from a list:

my_list = [1,2,4,6,7]

del my_list[1] # Removes index 1 from the list
print my_list # [1,4,6,7]
my_list.remove(4) # Removes the integer 4 from the list, not the index 4
print my_list # [1,6,7]
my_list.pop(2) # Removes index 2 from the list

In your case the appropriate method to use is pop, because it takes the index to be removed:

x = object()
y = object()
array = [x, y]
array.pop(0)
# Using the del statement
del array[0]
mkrieger1
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Ricardo Murillo
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    You should update the second part of your answer and have him use .pop(0) since he specifically asks about removing by position. – redreinard Dec 15 '14 at 21:02
  • When using `del array[0]` is removed` from the list but `x` itself still exists. Is there a method to remove `x` simultaneously (for example by deleting `x` by its pointer)? – Sajjad Mar 13 '20 at 08:44
7
del array[0]

where 0 is the index of the object in the list (there is no array in python)

MattoTodd
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6

If you want to remove multiple object from a list. There are various ways to delete an object from a list

Try this code. a is list with all object, b is list object you want to remove.

example :

a = [1,2,3,4,5,6]
b = [2,3]

for i in b:
   if i in a:
      a.remove(i)

print(a)

the output is [1,4,5,6] I hope, it will work for you

Muhammad Ammar Fauzan
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6

You could try this to dynamically remove an object from an array without looping through it? Where e and t are just random objects.

>>> e = {'b':1, 'w': 2}
>>> t = {'b':1, 'w': 3}
>>> p = [e,t]
>>> p
[{'b': 1, 'w': 2}, {'b': 1, 'w': 3}]
>>>
>>> p.pop(p.index({'b':1, 'w': 3}))
{'b': 1, 'w': 3}
>>> p
[{'b': 1, 'w': 2}]
>>>
BLang
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2

You can remove a string from an array like this:

array = ["Bob", "Same"]
array.remove("Bob")
Lil.Yeeet
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1

If we have an object x (e.g. an instance of some class X) that's in a list of other objects of the same type, we can simply directly remove it using list.remove(), provided the class has __eq__ properly implemented (this is already the case for built-in object types, but for custom classes always remember to implement the eq dunder function):

class X():
    def __init__(self, value=None):
        self.a = value
    def __eq__(self, other):
        if not hasattr(other, 'a'):
           return False
        return self.a == other.a

x = X(4)
y = X(10)
z = X(9)

my_list = [x,y,z]
print([e.a for e in a])
# prints [4, 10, 9]

my_list.remove(x)

print([e.a for e in a])
# prints [10, 9]
Mike 'Pomax' Kamermans
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0

if you wanna remove the last one just do your_list.pop(-1) if you wanna remove the first one your_list.pop(0) or any index you wish to remove

AngelloMaggio
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0

If you know the array location you can can pass it into itself. If you are removing multiple items I suggest you remove them in reverse order.

#Setup array
array = [55,126,555,2,36]
#Remove 55 which is in position 0
array.remove(array[0])
ZeroInputCtrl
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