如何使用dplyr根據另一列中的字符值的一部分更新列值？

Question

我有兩列的大型數據框。 我想根據左列中部分字符值來續訂右列。

這是一個例子：

df <- structure(list(content = c("my new info", "information2", 
"information3", "information4", "my new information2", "my new information3", 
"information5", "information6", "information7", "information8"
), content_new = c("no new info", "no new info", "no new info", 
"no new info", "no new info", "no new info", "no new info", "no new info", 
"no new info", "no new info")), .Names = c("content", "content_new"
), class = "data.frame", row.names = c(NA, 10L))

print(df)

               content content_new
1          my new info no new info
2         information2 no new info
3         information3 no new info
4         information4 no new info
5  my new information2 no new info
6  my new information3 no new info
7         information5 no new info
8         information6 no new info
9         information7 no new info
10        information8 no new info

這是我需要的結果：

               content         content_new
1          my new info         no new info
2         information2         no new info
3         information3         no new info
4         information4         no new info
5  my new information2 my new information2
6  my new informatino3 my new informatino3
7         information5         no new info
8         information6         no new info
9         information7         no new info
10        information8         no new info

我要實現的規則是：如果內容包括“新信息”，則將值放在content_new中。 我嘗試了這段代碼：

library(dplyr)
newdf <- mutate(df, content_new = ifelse(grepl("new information",content,fixed==FALSE) == TRUE,content,content_new)) 

我收到此錯誤：

Error in function (string)  : 
  comparison (1) is possible only for atomic and list types

有誰知道為什么會這樣以及我如何解決這個問題？ 提前謝謝了！

Answer 1

您必須使用fixed = FALSE而不是fixed == FALSE ：

mutate(df, content_new = ifelse(grepl("new information", content, fixed = FALSE),
                                content, content_new))
               content         content_new
1          my new info         no new info
2         information2         no new info
3         information3         no new info
4         information4         no new info
5  my new information2 my new information2
6  my new informatino3         no new info
7         information5         no new info
8         information6         no new info
9         information7         no new info
10        information8         no new info