在r中添加一个新的行和列

Question

I want to add a new value to the first column and first row of the data frame.

Sample of data:

  ali ata
1   u   w
2   y   e
3   t   r
4   f   x
5   s   z

Expected Results:

  ali ata
1  ttt  NA
2   u   w
3   y   e
4   t   r
5   f   x
6   s   z

Answer 1

Read the data. Here, it's important to encode strings as strings (not as factors):

df <- read.table(text="ali ata
1   u   w
2   y   e
3   t   r
4   f   x
5   s   z", header = TRUE, stringsAsFactors = FALSE)

You could use rbind to add the value:

rbind(c("ttt", rep(NA, ncol(df) - 1)), df)

   ali  ata
1  ttt <NA>
11   u    w
2    y    e
3    t    r
4    f    x
5    s    z