如何重塑R中数据的一部分

Question

我有一个如下所示的数据集：

df <- tibble::tribble(
  ~subcateg, ~names,
  "A00", "Kidney failure",
  "A001", "Kidney failure reason1",
  "A002", "Kidney failure reason2",
  "A003", "Kidney failure reason3",
  "B00", "Heart failure",
  "B001", "Heart failure reason1",
  "B002", "Heart failure reason2",
  "B003", "Heart failure reason3",
  "B00", "Lung failure",
  "B001", "Lung failure reason1",
  "B002", "Lung failure reason2",
  "B003", "Lung failure reason3",
)

它在同一个变量中有类别（3个字符）和子类别（4个字符），我需要另一个类别为3个字符的变量。我希望它看起来像这样：

df2 <- tibble::tribble(
  ~subcateg, ~names, ~categ, ~names2,
  "A001", "Kidney failure reason1", "A00", "Kidney failure",
  "A002", "Kidney failure reason2","A00", "Kidney failure",
  "A003", "Kidney failure reason3","A00", "Kidney failure",
  "B001", "Heart failure reason1",  "B00", "Heart failure",
  "B002", "Heart failure reason2",  "B00", "Heart failure",
  "B003", "Heart failure reason3",  "B00", "Heart failure",
  "B001", "Lung failure reason1",  "B00", "Lung failure",
  "B002", "Lung failure reason2",  "B00", "Lung failure",
  "B003", "Lung failure reason3",  "B00", "Lung failure",
)

有什么想法吗？非常感谢！

Answer 1

我们根据 'subcateg' 中出现的 3 个字符 (nchar) 创建一个分组变量，创建 'categ' 作为 first 元素20=]，删除第一行 (slice)，然后通过删除 reason 后跟 'names' 列

中的数字子字符串来创建 'names2'

library(dplyr)
library(stringr)
df %>% 
   group_by(grp = cumsum(nchar(subcateg) == 3)) %>%  
   mutate(categ = first(subcateg)) %>% 
   slice(if(n() == 1) 1 else -1)  %>% 
   ungroup %>% 
   select(-grp) %>%
   mutate(names2 = str_remove(names, "\s+reason\d+"))

-输出

# A tibble: 9 × 4
  subcateg names                  categ names2        
  <chr>    <chr>                  <chr> <chr>         
1 A001     Kidney failure reason1 A00   Kidney failure
2 A002     Kidney failure reason2 A00   Kidney failure
3 A003     Kidney failure reason3 A00   Kidney failure
4 B001     Heart failure reason1  B00   Heart failure 
5 B002     Heart failure reason2  B00   Heart failure 
6 B003     Heart failure reason3  B00   Heart failure 
7 B001     Lung failure reason1   B00   Lung failure  
8 B002     Lung failure reason2   B00   Lung failure  
9 B003     Lung failure reason3   B00   Lung failure

Answer 2

如果肺衰竭 类别以 C（而不是 B）开头——这是一个错误吗？ --，另一种解决方案如下：

library(tidyr)
library(dplyr)

df %>% 
  separate(subcateg,"categ",sep = "[1-9]", extra = "drop", remove = F) %>% 
  inner_join(df,by=c("categ" = "subcateg"),suffix = c("", "2")) %>% 
  filter(!stringr::str_ends(subcateg,"00")) %>% 
  relocate(categ, .after = names)

如何重塑R中数据的一部分

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