R 将具有特定值的新行添加到第一列，然后将添加到其余列

发布于07月28日

所以我有一个数据集，我想添加一个新行(其中有70多列).

以下是一个示例数据:

mydata = data.frame (Column1 =c("1","1","1","1","1","1","1",'1',"1","1"),
                     Column2 = c("2000-01-01","2000-01-05","2000-02-02", "2000-02-12", 
                              "2000-02-14","2000-05-13", "2000-05-15", "2000-05-17", 
                              "2000-05-16", "2000-05-20"),
                     Column3 = c("A","A","B","B","B","A","A","A","C","C"))

请看下面我的代码.这段代码允许我在第一列中添加一行，这让我很难在其他列中添加"-".我宁愿不列出每一列，因为我有70多列.

mydata <- mydata %>% bind_rows(list(`Column1` = "TORONTO"),.)

我try 了以下方法，但不断出错.


mydata <- mydata %>% bind_rows(list(`Column1` = "TORONTO"),col(2:ncol) = "-")

```

Any help would be appreciated!

推荐答案

我们可以用add_row

library(dplyr)
mydata %>%
  add_row(Column1 = "TORONTO", !!! setNames(rep('-', ncol(.)-1),
      names(.)[-1]))

-输出

   Column1    Column2 Column3
1        1 2000-01-01       A
2        1 2000-01-05       A
3        1 2000-02-02       B
4        1 2000-02-12       B
5        1 2000-02-14       B
6        1 2000-05-13       A
7        1 2000-05-15       A
8        1 2000-05-17       A
9        1 2000-05-16       C
10       1 2000-05-20       C
11 TORONTO          -       -

默认情况下，它在底部添加行.如果要在某个位置添加，请指定.before

mydata %>%
  add_row(Column1 = "TORONTO", !!! setNames(rep('-', ncol(.)-1),
      names(.)[-1]), .before = 1)

-输出

  Column1    Column2 Column3
1  TORONTO          -       -
2        1 2000-01-01       A
3        1 2000-01-05       A
4        1 2000-02-02       B
5        1 2000-02-12       B
6        1 2000-02-14       B
7        1 2000-05-13       A
8        1 2000-05-15       A
9        1 2000-05-17       A
10       1 2000-05-16       C
11       1 2000-05-20       C

或者可以使用summarise和across到c，将-作为第一个元素

mydata %>%
   summarise(Column1 = c("TORONTO", Column1), across(-Column1, ~ c("-", .x)))
   Column1    Column2 Column3
1  TORONTO          -       -
2        1 2000-01-01       A
3        1 2000-01-05       A
4        1 2000-02-02       B
5        1 2000-02-12       B
6        1 2000-02-14       B
7        1 2000-05-13       A
8        1 2000-05-15       A
9        1 2000-05-17       A
10       1 2000-05-16       C
11       1 2000-05-20       C