r - 根据逗号分割数据框列

Question

这个问题已经有答案了:

Split data frame string column into multiple columns (18 个回答)

已关闭 4 年前。

我有一个具有以下结构的数据框，标题为“final_proj_data”

ID          County              Population     Year  
<dbl>       <chr>               <dbl>          <dbl>    
1003    Baldwin County, Alabama 169162         2006     
1015    Calhoun County, Alabama 112903         2006     
1043    Cullman County, Alabama 80187          2006     
1049    DeKalb County, Alabama  68014          2006 

我试图将“县”列拆分为两个不同的列:“县”和“州”，并删除逗号。

我尝试了 split() 函数的多种排列，但我不断收到此错误:

Error: var must evaluate to a single number or a column name, not a character vector

我已经尝试过(除其他外)

  final_proj_data %>% 
separate(final_proj_data$County, c("State", "County"), sep = ",", remove = TRUE)
    final_proj_data %>% 
separate(data = final_proj_data, col = County,
 into = c("State", "County"), sep = ",")

我不确定我做错了什么，或者为什么“col =”不断抛出此错误。任何帮助将不胜感激!

Answer 1

使用dplyr和基础R:

library(dplyr)
 final_proj_data %>% 
 mutate(State=unlist(lapply(strsplit(County,", "),function(x) x[2])),
       County=gsub(",.*","",County))
    ID         County Population Year   State
1 1003 Baldwin County     169162 2006 Alabama
2 1015 Calhoun County     112903 2006 Alabama
3 1043 Cullman County      80187 2006 Alabama
4 1049  DeKalb County      68014 2006 Alabama

原文:

使用dplyr和tidyr(刚刚看到@Ronak Shah在上面评论了相同的内容):

library(dplyr)
library(tidyr)
final_proj_data %>% 
   separate(County,c("County","State"),sep=",")
    ID         County    State Population Year
1 1003 Baldwin County  Alabama     169162 2006
2 1015 Calhoun County  Alabama     112903 2006
3 1043 Cullman County  Alabama      80187 2006
4 1049  DeKalb County  Alabama      68014 2006