get elements that are present in list1 but not in list2 (like set operation A - B)

Question

I have two lists, list1 and list2, I want to get all elements that are present in list1 but not in list2. Currently, I am typecasting lists into set and subtracting them and then again typecasting result to list.

list(set(list1) - set(list2));

But this is not performance efficient. Can you please suggest me alternate ways to do the same thing?

score 0 · Answer 1 · answered Nov 23 '17 at 08:00

0

Using a list comprehension is probably simplest:

[x for x in list1 if not x in list2]

answered Nov 23 '17 at 08:00

C. Feenstra

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With simplicity, you should also check the performance. – bhansa Nov 23 '17 at 08:00
not working as expected. – Sachin Singh Nov 23 '17 at 08:08
I guess the duplicated marked question helps. – bhansa Nov 23 '17 at 08:16

get elements that are present in list1 but not in list2 (like set operation A - B)

1 Answers1