##### Find Common Elements in 2 list
 Find Common Elements in 2 list quest Wafer-Thin Wafer Posts: 82 Threads: 37 Joined: Nov 2020 Reputation: Apr-14-2021, 03:17 PM Hello I have this list: A [(7.5,), (17.5,), (22.5,), (25.0,), (27.5,), (30.0,), (37.5,), (40.0,)] B [(17.5,), (22.5,), (25.0,), (27.5,), (30.0,), (37.5,), (40.0,), (42.5,)] I want to find number of same elements in the list I tried these methods but the result is always zero: ```list1_as_set = set(A) intersection = list1_as_set.intersection(B) intersection_as_list = list(intersection)```I also tried that one: `commonalities = set(A) - (set(A) - set(B))`But the result is empty .. How can I find the common elements in 2 different list? Reply klllmmm Lumberjack Posts: 102 Threads: 38 Joined: Oct 2016 Reputation: Apr-14-2021, 03:29 PM Hope this helps ```A = [(7.5,), (17.5,), (22.5,), (25.0,), (27.5,), (30.0,), (37.5,), (40.0,)] B = [(17.5,), (22.5,), (25.0,), (27.5,), (30.0,), (37.5,), (40.0,), (42.5,)] list(set(A).intersection(B))`````Output:[(37.5,), (40.0,), (30.0,), (27.5,), (17.5,), (25.0,), (22.5,)]`` Reply Larz60+ aetate et sapientia Posts: 11,604 Threads: 449 Joined: Sep 2016 Reputation: Apr-14-2021, 03:31 PM ```>>> A = [(7.5,), (17.5,), (22.5,), (25.0,), (27.5,), (30.0,), (37.5,), (40.0,)] >>> B = [(17.5,), (22.5,), (25.0,), (27.5,), (30.0,), (37.5,), (40.0,), (42.5,)] >>> set(A).union(set(B)) {(37.5,), (40.0,), (30.0,), (27.5,), (17.5,), (7.5,), (42.5,), (25.0,), (22.5,)} >>> >>> >>> # With lists better formatted: >>> A = [7.5, 17.5, 22.5, 25.0, 27.5, 30.0, 37.5, 40.0] >>> B = [17.5 22.5, 25.0, 27.5, 30.0, 37.5, 40.0, 42.5] >>> set(A).union(set(B)) {37.5, 7.5, 40.0, 42.5, 17.5, 22.5, 25.0, 27.5, 30.0} >>>``` Reply quest Wafer-Thin Wafer Posts: 82 Threads: 37 Joined: Nov 2020 Reputation: Apr-14-2021, 03:33 PM (Apr-14-2021, 03:29 PM)klllmmm Wrote: Hope this helps ```A = [(7.5,), (17.5,), (22.5,), (25.0,), (27.5,), (30.0,), (37.5,), (40.0,)] B = [(17.5,), (22.5,), (25.0,), (27.5,), (30.0,), (37.5,), (40.0,), (42.5,)] list(set(A).intersection(B))`````Output:[(37.5,), (40.0,), (30.0,), (27.5,), (17.5,), (25.0,), (22.5,)]`` I have still empty list as a result ... Reply quest Wafer-Thin Wafer Posts: 82 Threads: 37 Joined: Nov 2020 Reputation: Apr-14-2021, 03:57 PM (Apr-14-2021, 03:29 PM)klllmmm Wrote: Hope this helps ```A = [(7.5,), (17.5,), (22.5,), (25.0,), (27.5,), (30.0,), (37.5,), (40.0,)] B = [(17.5,), (22.5,), (25.0,), (27.5,), (30.0,), (37.5,), (40.0,), (42.5,)] list(set(A).intersection(B))`````Output:[(37.5,), (40.0,), (30.0,), (27.5,), (17.5,), (25.0,), (22.5,)]``It is ok now THanks! klllmmm likes this post Reply

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