What is the the time complexity of each of python's set operations in Big O notation? I am using Python's set type for an operation on a large number of items. I want to know how each operation's

Apr 22, 2011 · I'd like to use Python's built-in set class with a custom class that I've created. If I want to create sets containing instances of my custom class, what functions do I need to implement so that I...

One possibility is to make use of the multiset module to precompute the multiset union of all elements in set_list, like so: from multiset import Multiset union = sum(set_list, Multiset()) set_list = [s - (union - s) for s in set_list] Here, union - s computes the Y ∪ Z ∪ A ∪ B... in your notation. See Aran-Fey's answer for the same method implemented (more verbosely) using only the ...

May 15, 2018 · So Python doesn't support the general, nebulous and infinite idea of a single universal set. For specific domains, if you can define the universal set in discrete terms, simply define your own complement() callable.

Jul 17, 2013 · While it is incredibly useful to be able to do set operations between the keys of a dictionary, I often wish that I could perform the set operations on the dictionaries themselves. I found some re...

Aug 12, 2019 · In Python, which data structure is more efficient/speedy? Assuming that order is not important to me and I would be checking for duplicates anyway, is a Python set slower than a Python list?

Feb 17, 2019 · (a|set([4]))-set([2]) So, my question is why is this happening and what is the operator (for set operators like -, |, &, ^, etc) precedence when applying set operations.

set.difference, set.union... can take any iterable as the second arg while both need to be sets to use -, there is no difference in the output. Operation Equivalent Result s.difference(t) s - t new set with elements in s but not in t With .difference you can do things like: s1 = set([1,2,3]) print(s1.difference(*[[3],[4],[5]])) {1, 2} It is also more efficient when creating sets using the ...

May 24, 2016 · I am looking for a single set operation to accomplish both the cases below. Is there a way to do this python? Case 1: a = set([1,2]) and b = set([1,2,3]) I want a result [1,2], which is a straightforward intersection. Now set(a) could be empty and performing intersection on empty set with any other set would lead to empty set. Case 2:

Apr 30, 2011 · The Python loop is much closer in performance than I would have expected, and you can get even closer by creating a local variable containing a reference to set.add and calling that in the loop, avoiding the attribute lookup.