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Youssef Moustahib
7,779 Points.difference does not work
Hi, I don't know why this Sint working:
a = {2,4,6,8} b = {1,2,3,4,5,6,7,8}
input: b.difference(a)
output: {1,3,5,7}
input: a.difference(b)
output: set()
Why do I keep getting set()?
2 Answers
Chels .
4,720 PointsYou're getting an empty set returned because .difference() shows what is different between the sets, in reference to the 1st set. a.difference() shows what values are unique to set a.
In b.difference(a), you're returned {1, 3, 5, 7} because those values are unique to b. They are not present in a.
When you call a.difference(b), it turns out there is nothing in set a that is not also in set b. Set a has values {2, 4, 6, 8}, which are also present in set b. Thus, you're being returned an empty set! Set a has no unique values when compared to set b.
Hope that helps!!
Steven Parker
229,771 PointsThat's an "empty set".
It shows that because "{}" would be an empty dictionary.