的R - GSUB功能

Question

編輯我有一個輸入數據幀是這樣的：

我所要的輸出是這樣的：

請找我的解釋下面。我真的不知道該給一個詳細的解釋超過了這個:(

讓我解釋一下....在輸入數據集，對於具有COL1值「10」行，我想掃描COL2價值觀，以「*」 ......同樣的邏輯也適用於具有重複COL1值的所有COL2值.. 我想使用GSUB功能的..

我更換任何重複的文本模式嘗試gsub連同粘貼幾次，我沒有得到所需的輸出，因爲我不知道如何匹配裏面的所有模式重複。

我已經問過這個問題。但由於我沒有收到答覆，我正在重新發布。

附加以下輸入數據框的dput：

structure(list(COL1 = c(10L, 10L, 10L, 20L, 20L, 30L, 30L, 40L, 
40L, 40L, 50L, 50L, 50L), COL2 = c("mary has life", "Don mary has life", 
"Britto mary has life", "push them fur", "push them ", "yell at this", 
"this is yell at this", "Year", "Doggy", "Horse", "This is great job", 
"great job", "Donkey")), .Names = c("COL1", "COL2"), row.names = c(NA, 
-13L), class = "data.frame") 

Answer 1

您可以編寫運行gsub一組中的每個項目，並選擇最短的更換功能（從本身不談，當然）：

fun <- function(col){ 
    matches <- sapply(col, function(x){gsub(x, '\\*', col)}); 
    diag(matches) <- NA; 
    apply(matches, 1, function(x){x[which.min(nchar(x))]}) 
} 

現在，在你最喜歡的語法實現：

library(dplyr) 

df %>% group_by(COL1) %>% mutate(COL3 = fun(COL2)) 

## Source: local data frame [13 x 3] 
## Groups: COL1 [5] 
## 
##  COL1     COL2   COL3 
## <int>    <chr>   <chr> 
## 1  10  mary has life mary has life 
## 2  10 Don mary has life   Don * 
## 3  10 Britto mary has life  Britto * 
## 4  20  push them fur   *fur 
## 5  20   push them  push them 
## 6  30   yell at this yell at this 
## 7  30 this is yell at this  this is * 
## 8  40     Year   Year 
## 9  40    Doggy   Doggy 
## 10 40    Horse   Horse 
## 11 50 This is great job  This is * 
## 12 50   great job  great job 
## 13 50    Donkey  Donkey 

或全部保留在底座R：

df$COL3 <- ave(df$COL2, df$COL1, FUN = fun) 

df 

## COL1     COL2   COL3 
## 1 10  mary has life mary has life 
## 2 10 Don mary has life   Don * 
## 3 10 Britto mary has life  Britto * 
## 4 20  push them fur   *fur 
## 5 20   push them  push them 
## 6 30   yell at this yell at this 
## 7 30 this is yell at this  this is * 
## 8 40     Year   Year 
## 9 40    Doggy   Doggy 
## 10 40    Horse   Horse 
## 11 50 This is great job  This is * 
## 12 50   great job  great job 
## 13 50    Donkey  Donkey