添加具有 ID 的列以匹配行

Question

我有如下数据：

library(data.table)
dat <- fread("Variable_codes_2022 Variables_2022
              Cat1_1              This_question
              Cat1_2              Other_question
              Cat2_1              One_question
              Cat2_2              Another_question
              Cat3_1              Some_question
              Cat3_2              Extra_question
              Cat3_3              This_question
              Cat4_1              One_question
              Cat4_2              Wrong_question")

我想做的是创建一个新列，它提供一个唯一的新变量代码，用于匹配变量。我从创建一个显示重复项的列开始，但这只会给TRUE 第二次出现而不是两者。此外，我仍然必须为 TRUE 值提供唯一名称。

dat$Common_codes_2022 <-  duplicated(dat[,2])

我应该怎么做？

期望的输出：

   Variable_codes_2022   Variables_2022 Common_codes_2022
1:              Cat1_1    This_question Com_1
2:              Cat1_2   Other_question
3:              Cat2_1     One_question Com_2
4:              Cat2_2 Another_question
5:              Cat3_1    Some_question
6:              Cat3_2   Extra_question
7:              Cat3_3    This_question Com_1
8:              Cat4_1     One_question Com_2
9:              Cat4_2   Wrong_question 

Answer 1

如果通用代码变量只是标记特定的Variables_2022 响应，您可以使用条件语句，例如这个case_when() 示例。

library(dplyr)
#> 
#> Attaching package: 'dplyr'
#> The following objects are masked from 'package:stats':
#> 
#>     filter, lag
#> The following objects are masked from 'package:base':
#> 
#>     intersect, setdiff, setequal, union
library(data.table)
#> 
#> Attaching package: 'data.table'
#> The following objects are masked from 'package:dplyr':
#> 
#>     between, first, last

dat <- fread("Variable_codes_2022 Variables_2022
              Cat1_1              This_question
              Cat1_2              Other_question
              Cat2_1              One_question
              Cat2_2              Another_question
              Cat3_1              Some_question
              Cat3_2              Extra_question
              Cat3_3              This_question
              Cat4_1              One_question
              Cat4_2              Wrong_question")

dat %>%
  mutate(Common_codes_2022 = case_when(
    Variables_2022 == "This_question" ~ "Com_1",
    Variables_2022 == "One_question" ~ "Com_2",
    TRUE ~ "")
  )
#>    Variable_codes_2022   Variables_2022 Common_codes_2022
#> 1:              Cat1_1    This_question             Com_1
#> 2:              Cat1_2   Other_question                  
#> 3:              Cat2_1     One_question             Com_2
#> 4:              Cat2_2 Another_question                  
#> 5:              Cat3_1    Some_question                  
#> 6:              Cat3_2   Extra_question                  
#> 7:              Cat3_3    This_question             Com_1
#> 8:              Cat4_1     One_question             Com_2
#> 9:              Cat4_2   Wrong_question

^{创建于 2022 年 11 月 12 日，reprex v2.0.2}