r - 将列名转换为 R 中数据框的第一行

Question

我想更改现有数据框的列名而不删除它。

我需要将这些列名作为数据框的第一行。

eg.

Existing dataframe 

df = data.frame(x = c("P1","P2","P3","P4","P5"),
                y = c("DC","DC","DC","DC","DC"),
                f_1 = c("NA","1","NA","NA","NA"), 
                f_2= c("NA","1","NA","NA","NA"),
                f_3= c("1","7","NA","NA","NA"),
                f_4= c("NA","NA","5","NA","NA"),
                f_5= c("NA","NA","2","NA","NA"),
                stringsAsFactors = FALSE)

I want to change those col names with another data frame column names.

df1 = data.frame(A = c("P1"),
                 B = c("p2"),
                C = c("p3"), 
                D= c("p4"),
                E= c("p8"),
                F= c("p9"),
                G= c("p8"),
                stringsAsFactors = FALSE)

要求的输出:

Df
    
        
        A    B    C    D    E    F    G
    1   x    y   f_1  f_2   f_3  f_4  f_5
    2   P1  DC   NA   NA    1    NA   NA
    3   P2  DC   1    1     7    NA   NA 
    4   P3  DC   NA   NA    NA   5    2
    5   P4  DC   NA   NA    NA   NA   NA
    6   P5  DC   NA   NA    NA   NA   NA

我试过了，但不正确。

df1<-as.data.frame(t(as.character(unlist(colnames(df1)))))
  
colnames(df1) <- df[1,]

有人知道正确的方法吗？？

Answer 1

在base R中，只需rbind第一个数据的列名，然后设置列名

setNames(rbind(names(df), df), names(df1))
#  A  B   C   D   E   F   G
#1  x  y f_1 f_2 f_3 f_4 f_5
#2 P1 DC  NA  NA   1  NA  NA
#3 P2 DC   1   1   7  NA  NA
#4 P3 DC  NA  NA  NA   5   2
#5 P4 DC  NA  NA  NA  NA  NA
#6 P5 DC  NA  NA  NA  NA  NA