Remove Items from One List in Another

Remove item from one list if NOT in another list?

Assuming playing is a list of strings corresponding to player names:

bedwarsPoints = [i for i in bedwarsPoints if i[0] in playing]

remove elements of one list from another list python

I would use a counter of the elements to be removed.

So, something like

from collections import Counter 

data = [1, 2, 2, 3, 3, 3]
to_be_removed = [1, 2, 3, 3] # notice the extra 3

counts = Counter(to_be_removed)

new_data = []
for x in data:
    if counts[x]:
        counts[x] -= 1
    else:
        new_data.append(x)

print(new_data)

This solution is linear time / space. If you actually need to modify the list (which is code-smell, IMO), you would require quadratic time

Note, consider if you actually just want a multiset - i.e. you could just be working with counters all along, consider:

>>> Counter(data) - Counter(to_be_removed)
Counter({2: 1, 3: 1})

Remove items from one list in another

You can use Except:

List<car> list1 = GetTheList();
List<car> list2 = GetSomeOtherList();
List<car> result = list2.Except(list1).ToList();

You probably don't even need those temporary variables:

List<car> result = GetSomeOtherList().Except(GetTheList()).ToList();

Note that Except does not modify either list - it creates a new list with the result.

How to Remove elements from one List based another list's element and condition?

You can remove the elements like this:

list1.RemoveAll(item => list2.Any(item2 => item.Key == item2.Key))

How to remove all items in a list that are in another list in Python 3?

Use the filter function to filter out any items present in both lists like this:

def array_diff(a, b):    
    return list(filter(lambda item: item not in ls2, ls1))

ls1 = [1, 2, 3, 4, 5]
ls2 = [2, 5]
print(array_diff(ls1, ls2))

Remove elements from list that is in another list while keeping duplicates

you need a little bit more complex loops:

l1 = ['a', 'b', 'b', 'a', 'c', 'c', 'a']
l2 = ['c', 'b']
l3=[]
for item in l1:
    if item in l2:
        l2.remove(item)
    else:
        l3.append(item)
>>>l3
['a', 'b', 'a', 'c', 'a']

remove elements in one list present in another list

Use list comprehension:

>>> list1 = ['paste', 'text', 'text', 'here', 'here', 'here', 'my', 'i', 'i', 'me', 'me']
>>> list2 = ["i","me"]
>>> list3 = [item for item in list1 if item not in list2]
>>> list3
['paste', 'text', 'text', 'here', 'here', 'here', 'my']

NOTE: Lookups in lists are O(n), consider making a set from list2 instead - lookups in sets are O(1).

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