r - 如何更改 R data.frame 中的行名称？

Question

我想将 DF 中的 station 重命名为 DA056至 Happy和 AB786至 Sad .

library(tidyverse)

DF1 <- data.frame(Station = rep("DA056",3), Level = 100:102) 
DF2 <- data.frame(Station = rep("AB786",3), Level = 201:203) 
DF <- bind_rows(DF1,DF2)

Answer 1

我们可以使用 factor与 labels指定为相应的 levels

library(dplyr)
DF <- DF %>%
    mutate(Station = factor(Station, levels = c("DA056", "AB786"), 
              labels = c("Happy", "Sad")))

DF$Station
#[1] Happy Happy Happy Sad   Sad   Sad  
#Levels: Happy Sad

或与 recode

DF %>%
     mutate(Station = recode(Station, DA056 = 'Happy', AB786 = 'Sad'))
#  Station Level
#1   Happy   100
#2   Happy   101
#3   Happy   102
#4     Sad   201
#5     Sad   202
#6     Sad   203

如果要更改的值很多，更好的选择是在创建 key/val 数据集后加入

keyval <- data.frame(Station = c("DA056", "AB786"),
    val = c("Happy", "Sad"), stringsAsFactors = FALSE)
DF %>%
     left_join(keyval) %>%
     mutate(Station = coalesce(val, Station))

或与 base R

DF$Station <- with(df,  factor(Station, levels = c("DA056", "AB786"), 
              labels = c("Happy", "Sad")))