我有一个组，它假定每个元素有2行。对于其中一些，我只有1行，我想选择此行。
dput(r[40:46,1:6])
structure(list(SAMPN = c(" 25", " 25", " 27", " 29",
" 29", " 29"), MODE1 = structure(c(2L, 2L, 4L, 1L, 1L, 1L
), .Label = c("1", "2", "3", "4"), class = "factor"), HHVEH = structure(c(3L,
3L, 2L, 1L, 1L, 1L), .Label = c("0", "1", "2", "3", "4", "5",
"6", "7", "8"), class = "factor"), PERNO = structure(c(2L, 2L,
1L, 1L, 1L, 1L), .Label = c("1", "2", "3", "4", "5", "6", "7"
), class = "factor"), PLANO = structure(c(1L, 2L, 1L, 1L, 2L,
3L), .Label = c(" 2", " 3", " 4", " 5", " 6", " 7", " 8", " 9",
"10", "11", "12", "13", "14", "15", "16", "17", "18", "20", "23",
"25", "29"), class = "factor"), loop = structure(c(2L, 2L, 2L,
2L, 2L, 3L), .Label = c("1", "2", "3", "4", "5", "6", "7", "8"
), class = "factor")), row.names = c(NA, -6L), groups = structure(list(
SAMPN = c(" 25", " 27", " 29", " 29"), PERNO = structure(c(2L,
1L, 1L, 1L), .Label = c("1", "2", "3", "4", "5", "6", "7"
), class = "factor"), loop = structure(c(2L, 2L, 2L, 3L), .Label = c("1",
"2", "3", "4", "5", "6", "7", "8"), class = "factor"), .rows = list(
1:2, 3L, 4:5, 6L)), row.names = c(NA, -4L), class = c("tbl_df",
"tbl", "data.frame"), .drop = TRUE), class = c("grouped_df",
"tbl_df", "tbl", "data.frame"))
SAMPN MODE1 HHVEH PERNO PLANO loop
<chr> <fct> <fct> <fct> <fct> <fct>
1 " 25" 2 2 2 " 2" 2
2 " 25" 2 2 2 " 3" 2
3 " 27" 4 1 1 " 2" 2
4 " 29" 1 0 1 " 2" 2
5 " 29" 1 0 1 " 3" 2
6 " 29" 1 0 1 " 4" 3
如果SAMPN，PERNO和循环相同并且只有一行而不是两行，我想删除行。在上面的示例中，我需要选择第3行和第6行。