删除矩阵中的行

Question

我有一个矩阵,看起来像这样:

have=rbind(matrix(c(1,1,1,1,2,2,2,2,3,3,3,3),ncol=3),c(5,5,5),c(5,5,5),c(5,5,5),c(1,1,1),c(1,1,1))

      [,1] [,2] [,3]
 [1,]    1    2    3
 [2,]    1    2    3
 [3,]    1    2    3
 [4,]    1    2    3
 [5,]    5    5    5
 [6,]    5    5    5
 [7,]    5    5    5
 [8,]    1    1    1
 [9,]    1    1    1

我想删除行,如果他们只出现1或2次.理想情况下,我希望它是用户特定的,因此如果该行仅出现N次或更少,则应删除它.所以,如果N = 2那么它应该删除最后两行,因为它们只出现两次:

want=rbind(matrix(c(1,1,1,1,2,2,2,2,3,3,3,3),ncol=3),c(5,5,5),c(5,5,5),c(5,5,5))

     [,1] [,2] [,3]
[1,]    1    2    3
[2,]    1    2    3
[3,]    1    2    3
[4,]    1    2    3
[5,]    5    5    5
[6,]    5    5    5
[7,]    5    5    5

另一方面,如果N = 3,那么它应该返回:

want_2=rbind(matrix(c(1,1,1,1,2,2,2,2,3,3,3,3),ncol=3))

     [,1] [,2] [,3]
[1,]    1    2    3
[2,]    1    2    3
[3,]    1    2    3
[4,]    1    2    3

Answer 1

rowRemove <- function(x, n) {
  oc <- apply(x, 1, paste, collapse = "\r")
  x[table(oc)[oc] > n, ]
}
rowRemove(have, 3)
#      [,1] [,2] [,3]
# [1,]    1    2    3
# [2,]    1    2    3
# [3,]    1    2    3
# [4,]    1    2    3