如何从 R 中的“setequally”列表中删除重复元素？

Question

Suppose I have some list li in R whose elements are vectors. For instance,

li=list(a=c(2,3,5),b=c(77,119,81),c=c(9,11,13),d=c(5,2,3),e=c(80,45,16),f=c(16,17,19),g=c(13,9,11),h=c(22,13,58)) 

It can be seen that all objects in li are different as vectors . Therefore,

duplicated(li)
[1] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE

Also, the command unique(li) will return the same list li . But note that the elements a and d as well as c and g are equal as sets . Namely,

setequal(li$a,li$d)
[1] TRUE

and

setequal(li$c,li$g)
[1] TRUE

Consequently, the element a is duplicated as set by the element d and the element c is duplicated as set by the element g. My question is: How to remove from a list such 'setequally' duplicated elements in R ?

Answer 1

What about:

li[apply(sapply(li, function(x) sapply(li, setequal, x)), 2, sum)==1]

$b
[1]  77 119  81

$e
[1] 80 45 16

$f
[1] 16 17 19

$h
[1] 22 13 58

?

Answer 2

We can get the unique sort ed elements and then remove all the set equal elements with duplicated

li1 <- lapply(li, function(x) sort(unique(x)))
i1 <- !(duplicated(li1)|duplicated(li1, fromLast = TRUE))
li[i1]
#$b
#[1]  77 119  81

#$e
#[1] 80 45 16

#$f
#[1] 16 17 19

#$h
#[1] 22 13 58