正则表达式在第二个管道之后和第二个 T 之后拆分 R 中的列

Question

我有一个包含数千行的 1 列数据框，全部基于相同的模式构建，例如：

ids <- c("ETC|HMPI01000001|HMPI01000001.1 TAG: Genus Species, T05X3Ml2_CL10007Cordes1_1","ETC|HMPI31000002|HMPI31000002.1 TAG: Genus Species, T3X3Ml2_CL10157Cordes1_1", "ETC|HMPI01000007|HMPI01000007.1 TAG: Genus Species, T1X3Ml2_CL11231Cordes1_1")

df <- as.data.frame(ids)

> df
                                                                            ids
1  ETC|HMPI01000001|HMPI01000001.1 TAG: Genus Species, T05X3Ml2_CL10007Cordes1_1
2  ETC|HMPI31000002|HMPI31000002.1 TAG: Genus Species, T3X3Ml2_CL10157Cordes1_1
3  ETC|HMPI01000007|HMPI01000007.1 TAG: Genus Species, T1X3Ml2_CL11231Cordes1_1

我想将这些字符分成两列： var1 和 var2 这样，并保留第二个管道之后和第一个空格之前的文本，以及空格之后第二个 T 中的文本。这些将是所有线路的共同模式。预期结果是：

> df
            var1                      var2
1 HMPI01000001.1 T05X3Ml2_CL10007Cordes1_1
2 HMPI31000002.1  T3X3Ml2_CL10157Cordes1_1
3 HMPI01000007.1  T1X3Ml2_CL11231Cordes1_1

我尝试了几个受这里、那里或那里启发的正则表达式..但我无法弄清楚。

我目前有这个，但它没有给出预期的结果：

df2 <- df %>% separate(col = "ids", into = c("var1", "var2"), sep = "\\|([^|]+)$")
> df2
              var1 var2
1 ETC|HMPI01000001     
2 ETC|HMPI31000002     
3 ETC|HMPI01000007   

任何帮助，最好使用正则表达式和 tidyverse，将不胜感激。

Answer 1

我们可以用strcapture。

strcapture("^[^|]*\\|[^|]*\\|(\\S+)\\s.*? (T.*)",
           ids, list(var1="", var2=""))
#             var1                      var2
# 1 HMPI01000001.1 T05X3Ml2_CL10007Cordes1_1
# 2 HMPI31000002.1  T3X3Ml2_CL10157Cordes1_1
# 3 HMPI01000007.1  T1X3Ml2_CL11231Cordes1_1

正则表达式：

"^[^|]*\\|[^|]*\\|(\\S+)\\s.*? (T.*)"
 ^                                     beginning of string
  [^|]*\\|                             leading up to first |
          [^|]*\\|                     leading up to the second |
                  (\\S+)\\s            non-space (captured) and blank space
                           .*?         non-greedy "anything"
                               (T.*)   literal T (after a space) and everything else

Answer 2

library(stringr)
library(dplyr)

df |>
  mutate(var1 = str_extract(ids, ".*\\|(\\S+)", group = 1),
         var2 = str_extract(ids, ".*, (.*$)", group = 1))

separate_wider_position如果它们的位置是固定的，您也可以使用：

library(tidyr)

df |>
  separate_wider_position(ids, 
                          widths = c(17, var1 = 14, 21, var2 = max(nchar(ids))), 
                          too_few = "align_start")

#  var1           var2                     
#  <chr>          <chr>                    
# 1 HMPI01000001.1 T05X3Ml2_CL10007Cordes1_1
# 2 HMPI31000002.1 T3X3Ml2_CL10157Cordes1_1 
# 3 HMPI01000007.1 T1X3Ml2_CL11231Cordes1_1