从 R 中的另一个字符串列条件的字符串列中删除所有内容

Question

我试图清理一个包含辩论期间长篇演讲的专栏。 现在，每一行都以一个新的演讲者开始，但是，副标题之类的东西保留在每个演讲的结尾，这是不可取的。

以下是一些示例数据：

speeches <- tibble(subheader = c("3.Discussion", "8.Voting"),
                   full_speech = c("I close this part. 3.Discussion Let's start with",
                                   "I think we can vote now")
                   )

期望的结果：

subheader      full_speech
3. Discussion  I close this part.
8. Voting      I think we can vote now

到目前为止我尝试了什么：

speeches %>%
    mutate(full_speech = str_remove(full_speech, subheader))

但是当然这只会删除子标题而不是它们之后的内容。

Answer 1

我们可以用.*粘贴subheader以匹配子标题后的任何字符

library(dplyr)
library(stringr)
speeches %>% 
  mutate(full_speech = str_remove(full_speech, str_c("\\s+", 
      subheader, ".*")))

-输出

# A tibble: 2 × 2
  subheader    full_speech            
  <chr>        <chr>                  
1 3.Discussion I close this part.     
2 8.Voting     I think we can vote now

Answer 2

一种使用sub和paste从subheader构造替换的方法。

library(dplyr)

speeches %>% 
  rowwise() %>%
  mutate(full_speech = gsub(
           paste0(" ", subheader, ".*", collapse=""), "", full_speech)) %>% 
  ungroup()
# A tibble: 2 × 2
  subheader    full_speech            
  <chr>        <chr>                  
1 3.Discussion I close this part.     
2 8.Voting     I think we can vote now