합집합,교집합,차집합 in r
R
2 vector
A <- c(1,2,3,4,5) B <- c(4,5,6,7,8)
합집합 (A∪B)
> unique(c(A,B)) [1] 1 2 3 4 5 6 7 8
교집합(A∩B)
> A[A%in%B] > B[B%in%A] > intersect(A,B) [1] 4 5
차집합(A-B)
> A[!(A%in%B)] [1] 1 2 3
Multi-vector
https://www.r-bloggers.com/intersect-for-multiple-vectors-in-r/
Reduce(intersect, list(a,b,c))
Reduce(union, list(x, y, z))
reduce()
combine from the left
R