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具有正lookhead的Regex仍然使用strsplit()在错误的位置拆分字符串

strsplit regex-lookarounds pcre regex r

Ju Ko · 技术社区 · 8 年前

我正在尝试拆分包含消息的字符向量,对吗 在前面 日期时间指示器的。

我在考虑使用 strsplit() 使用正则表达式和 perl = TRUE

以下是一些示例数据:

TEST <- c("05.10.17, 09:26 - Person One: How about we chill on sunday\n05.10.17, 09:27 - Person One: I could bring some beer\n05.10.17, 09:27 - Person Two: Sounds good, we could go to Lindas Party afterwards\n05.10.17, 09:27 - Person One: shit man, not LiNDA -.-\n05.10.17, 09:27 - Person Two: ???\n05.10.17, 09:28 - Person Two: You guys have history?\n05.10.17, 09:28 - Person One: She killed my family and sold their ears as souvenirs\n")

这就是我迄今为止所尝试的:

Cut <- unlist(strsplit(TEST,"(?=[0-3][0-9][.][0-9]{2}[.][0-9]{2}[,][ ][0-9]{2}:[0-9]{2})", perl = TRUE))
Cut

根据 this website ,正则表达式应该在日期时间指示器的正前方剪切字符串。然而,我得到的结果是这样的,第一个角色被切掉了:

 [1] "0"                                                                                   
 [2] "5.10.17, 09:26 - Person One: How about we chill on sunday\n"                         
 [3] "0"                                                                                   
 [4] "5.10.17, 09:27 - Person One: I could bring some beer\n"                              
 [5] "0"                                                                                   
 [6] "5.10.17, 09:27 - Person Two: Sounds good, we could go to Lindas Party afterwards\n"  
 [7] "0"                                                                                   
 [8] "5.10.17, 09:27 - Person One: shit man, not LiNDA -.-\n"                              
 [9] "0"                                                                                   
[10] "5.10.17, 09:27 - Person Two: ???"                                                                   
[11] "0"                                                                                   
[12] "5.10.17, 09:28 - Person Two: You guys have history?\n"                               
[13] "0"                                                                                   
[14] "5.10.17, 09:28 - Person One: She killed my family and sold their ears as souvenirs\n"

这就是结果应该看起来像:

 [1] "05.10.17, 09:26 - Person One: How about we chill on sunday\n"                                                                                   
 [2] "05.10.17, 09:27 - Person One: I could bring some beer\n"                         
 [3] "05.10.17, 09:27 - Person Two: Sounds good, we could go to Lindas Party afterwards\n"                                                                                   
 [4] "05.10.17, 09:27 - Person One: shit man, not LiNDA -.-\n"                              
 [5] "05.10.17, 09:27 - Person Two: ???\n"                                                                                   
 [6] "05.10.17, 09:28 - Person Two: You guys have history?\n"  
 [7] 05.10.17, 09:28 - Person One: She killed my family and sold their ears as souvenirs\n"

注意:我不能在换行符处拆分数据,因为某些消息包含消息中间的一个或多个数据。

3 回复 | 直到 8 年前

Onyambu 8 年前

您只需在以下情况下创建拆分模式 \n 后跟日期。

 strsplit(gsub("(.*?\\n)(\\d+[.]\\d+[.]\\d+)","\\1SPLITHERE\\2",TEST),"SPLITHERE")
[[1]]
[1] "05.10.17, 09:26 - Person One: How about we chill on sunday\n"                         
[2] "05.10.17, 09:27 - Person One: I could bring some beer\n"                              
[3] "05.10.17, 09:27 - Person Two: Sounds good, we could go to Lindas Party afterwards\n"  
[4] "05.10.17, 09:27 - Person One: shit man, not LiNDA -.-\n"                              
[5] "05.10.17, 09:27 - Person Two: ???\n"                                                  
[6] "05.10.17, 09:28 - Person Two: You guys have history?\n"                               
[7] "05.10.17, 09:28 - Person One: She killed my family and sold their ears as souvenirs\n"

您还可以使用 rematches 从底部r

 regmatches(TEST,gregexpr(".*?\\n",TEST))
[[1]]
[1] "05.10.17, 09:26 - Person One: How about we chill on sunday\n"                         
[2] "05.10.17, 09:27 - Person One: I could bring some beer\n"                              
[3] "05.10.17, 09:27 - Person Two: Sounds good, we could go to Lindas Party afterwards\n"  
[4] "05.10.17, 09:27 - Person One: shit man, not LiNDA -.-\n"                              
[5] "05.10.17, 09:27 - Person Two: ???\n"                                                  
[6] "05.10.17, 09:28 - Person Two: You guys have history?\n"                               
[7] "05.10.17, 09:28 - Person One: She killed my family and sold their ears as souvenirs\n"

Gilles San Martin 8 年前

可以添加白色字符类 \\s 在你积极展望之前。

我稍微更改了您的示例,使其更精确地匹配您的问题(即在标题中添加)

> TEST <- c("05.10.17, 09:26 - Person One: How about\n we chill on sunday\n05.10.17, 09:27 - Person One: I could bring some beer\n05.10.17, 09:27 - Person Two: Sounds good, we could go to Lindas Party afterwards\n05.10.17, 09:27 - Person One: shit man, not LiNDA -.-\n05.10.17, 09:27 - Person Two: ???\n05.10.17, 09:28 - Person Two: You guys have history?\n05.10.17, 09:28 - Person One: She killed my family and sold their ears as souvenirs\n")
> unlist(strsplit(TEST,"\\s(?=[0-3][0-9][.][0-9]{2}[.][0-9]{2}[,][ ][0-9]{2}:[0-9]{2})", perl = TRUE))

## [1] "05.10.17, 09:26 - Person One: How about\n we chill on sunday"                         
## [2] "05.10.17, 09:27 - Person One: I could bring some beer"                                
## [3] "05.10.17, 09:27 - Person Two: Sounds good, we could go to Lindas Party afterwards"    
## [4] "05.10.17, 09:27 - Person One: shit man, not LiNDA -.-"                                
## [5] "05.10.17, 09:27 - Person Two: ???"                                                    
## [6] "05.10.17, 09:28 - Person Two: You guys have history?"                                 
## [7] "05.10.17, 09:28 - Person One: She killed my family and sold their ears as souvenirs\n"

Shenglin Chen 8 年前

strsplit(TEST, '(?<=\\\n|^)(0)',perl=T)[[1]][2:7]