将列中的值转换为R中的现有数据帧中的行名

I would like to convert the values in a column of an existing data frame into row names. Is is possible to do this without exporting the data frame and then reimporting it with a row.names = call?

我希望将现有数据帧的列中的值转换为行名称。是否可以不导出数据帧，然后使用row.names =调用重新导入数据帧?

For example I would like to convert:

例如，我想要转换:

 > samp 
     names Var.1 Var.2 Var.3
 1     A     1     5     0
 2     B     2     4     1
 3     C     3     3     2
 4     D     4     2     3
 5     E     5     1     4

into:

成:

> samp.with.rownames 
     Var.1 Var.2 Var.3
A     1     5     0
B     2     4     1
C     3     3     2
D     4     2     3
E     5     1     4

thanks

谢谢

4 个解决方案

#1

This should do:

这个应该做的是:

samp2 <- samp[,-1]
rownames(samp2) <- samp[,1]

So in short, no there is no alternative to reassigning.

所以简而言之，没有任何替代选择。

Edit: Correcting myself, one can also do it in place: assign rowname attributes, then remove column:

编辑:纠正自己，你也可以这样做:分配rowname属性，然后删除列:

R> df<-data.frame(a=letters[1:10], b=1:10, c=LETTERS[1:10])
R> rownames(df) <- df[,1]
R> df[,1] <- NULL
R> df
   b c
a  1 A
b  2 B
c  3 C
d  4 D
e  5 E
f  6 F
g  7 G
h  8 H
i  9 I
j 10 J
R>

#2

in one line

在一行

> samp.with.rownames <- data.frame(samp[,-1], row.names=samp[,1])

#3

As of 2016 you can also use the tidyverse.

到2016年，你也可以使用tidyverse。

library(tidyverse)
samp %>% remove_rownames %>% column_to_rownames(var="names")

#4

You can execute this in 2 simple statements:

你可以用两个简单的语句来执行:

row.names(samp) <- samp$names
samp[1] <- NULL

#1