将字符串分成3列：文本，数字，文本

Question

我正在处理一个大型数据集（约1500行），并且当我构建数据集时，我没有想到提前分离我的标识符，所以它们是集中成一个长串。

标识字符串位于标有“Polygon_Name”的列中。我想保留此列，并将此列中的字符串值拆分为3个附加列。例如，如果任何“Polygon_Name”单元格中嵌入了一个数字，比如Canker14B，我想最终得到以下列：（1）原始的Polygon_Name，（2）之前的所有文本号码，（3）号码，（4）号码后的全部文本。

我的数据的小部分：

df <- structure(list(Bolt_ID = structure(c(1L, 1L, 1L, 1L, 1L, 1L, 
1L, 1L, 1L, 1L), .Label = "N1T.3.4.15.0.C", class = "factor"), 
    Polygon_Name = structure(c(10L, 1L, 9L, 6L, 3L, 7L, 2L, 8L, 
    4L, 5L), .Label = c("C", "Canker15B", "Canker15Left", "Canker15Right", 
    "Canker16", "Canker17", "CankS15B", "CankS16", "CankS17", 
    "S"), class = "factor"), Measure = c(19.342, 25.962, 0.408, 
    0.008, 0.074, 0.41, 0.011, 0.251, 0.056, 0.034)), .Names = c("Bolt_ID", 
"Polygon_Name", "Measure"), row.names = c(1L, 2L, 4L, 5L, 6L, 
7L, 8L, 9L, 10L, 11L), class = "data.frame") 

电流输出：

最终输出（I这个手动建立）：

我已经想出了如何提取用下面的代码数量：

library(stringr) 
regexp <- "[[:digit:]]+" 
df$Poly_Num <- str_extract(df$Polygon_Name, regexp) 

但我仍然在努力前后数后拉出来的文字。任何想法将不胜感激。

Answer 1

通过tidyverse一个想法是，

library(tidyverse) 

df %>% 
mutate(Poly_num = gsub('\\D+', '', Polygon_Name)) %>% 
separate(Polygon_Name, into = c('Poly_type', 'Poly_letter'), sep = '[0-9]+', remove = FALSE) 

#   Bolt_ID Polygon_Name Poly_type Poly_letter Measure Poly_num 
#1 N1T.3.4.15.0.C    S   S  <NA> 19.342   
#2 N1T.3.4.15.0.C    C   C  <NA> 25.962   
#3 N1T.3.4.15.0.C  CankS17  CankS    0.408  17 
#4 N1T.3.4.15.0.C  Canker17 Canker    0.008  17 
#5 N1T.3.4.15.0.C Canker15Left Canker  Left 0.074  15 
#6 N1T.3.4.15.0.C  CankS15B  CankS   B 0.410  15 
#7 N1T.3.4.15.0.C  Canker15B Canker   B 0.011  15 
#8 N1T.3.4.15.0.C  CankS16  CankS    0.251  16 
#9 N1T.3.4.15.0.C Canker15Right Canker  Right 0.056  15 
#10 N1T.3.4.15.0.C  Canker16 Canker    0.034  16 

一个班轮将是既然你已经使用stringr使用extract从tidyr（@docendodiscimus致意）

tidyr::extract(df, Polygon_Name, c("a","b","c"), "^([^0-9]+)(\\d*)([^0-9]*)$", 
                 remove = FALSE, convert = TRUE) 

Answer 2

，你可以得到这些使用str_match

str_match(df$Polygon_Name, "([[:alpha:]]*)([[:digit:]]*)([[:alpha:]]*)")[,2:4] 
     [,1]  [,2] [,3] 
[1,] "S"  "" ""  
[2,] "C"  "" ""  
[3,] "CankS" "17" ""  
[4,] "Canker" "17" ""  
[5,] "Canker" "15" "Left" 
[6,] "CankS" "15" "B"  
[7,] "Canker" "15" "B"  
[8,] "CankS" "16" ""  
[9,] "Canker" "15" "Right" 
[10,] "Canker" "16" "" 

要将此添加到您现有的数据帧中，您可以使用

PName = str_match(df$Polygon_Name, "([[:alpha:]]*)([[:digit:]]*)([[:alpha:]]*)")[,2:4] 
df = data.frame(df, PName) 
names(df)[4:6] = c("Poly_Type", "Poly_Num", "Poly_Letter")