r - 提取多个列表中的常用名称

Question

大家早上好

我有四个“字符”类列表:

list1 <- c("hola1", "hola2", "hola3")
list2 <- c("hola1", "hola2", "hola4")
list3 <- c("hola2", "hola7", "hola8")
list4 <- c("hola1", "hola7", "hola8")

我想获得这些列表之间有多少项是共同的，就像维恩图一样，所以输出:

Between list1 and list2: hola1 and hola2 are common names. Between list1 and list3: hola2 is a common name. Among list1, list2, and list4: hola1 is a common name.

或者换句话说，类似的东西:

是这样的。你知道任何包或获取方法吗？

提前致谢。

Answer 1

您可以将intersect 与combn 结合使用。 intersect 查找公共(public)元素，combn 会将其应用于列表的所有 1vs1 组合:

l <- list(c("hola1", "hola2", "hola3"),
          c("hola1", "hola2", "hola4"),
          c("hola2", "hola7", "hola8"),
          c("hola1", "hola7", "hola8"))

combn(length(l), 2, FUN=function(i)intersect(l[[i[1]]], l[[i[2]]]),
      simplify=FALSE)
# [[1]]
# [1] "hola1" "hola2"
#[[2]]
#[1] "hola2"
#[[3]]
#[1] "hola1"
#[[4]]
#[1] "hola2"
#[[5]]
#[1] "hola1"
#[[6]]
#[1] "hola7" "hola8"