求助！R语言如何替换另外一段字符

想问一下 如何实现一下的replace_one_phrase 和 replace_phrases 这两段代码


replace_one_phrase <- function (text, phrase)
> t <- c("I","like","hot","dogs","a","lot","hot","dogs","forever")
> t
[1] "I" "like" "hot" "dogs" "a" "lot" "hot"
[8] "dogs" "forever"
> replace_one_phrase(t,c("hot","dogs"))
[1] "I" "like" "hot_dogs" "a" "lot" "hot_dogs" "forever"

> replace_phrases (c("ab","pq","xy"), list(c("ab","pq"),c("pq","xy")))
[1] "ab_pq" "xy"

1. t <- c("I","like","hot","dogs","a","lot","hot","dogs","forever")
   
2. 
   
3. replace_one_phrase <- function(x, phrase) {
   
4.   if (length(x) < length(phrase)) return(x)
   
5.   n <- length(phrase)
   
6.   if (identical(x[1:n], phrase)) {
   
7.     return(c(paste(phrase, collapse = "_"), replace_one_phrase(x[-(1:n)], phrase)))
   
8.   }
   
9.   return(c(x[1], replace_one_phrase(x[-1], phrase)))
   
10. }
    
11. 
    
12. replace_one_phrase(t, c("hot", "dogs"))
    
13. 
    
14. replace_phrases <- function(x, phrases) {
    
15.   for (phrase in phrases) {
    
16.     x <- replace_one_phrase(x, phrase)
    
17.   }
    
18.   x
    
19. }
    
20. 
    
21. replace_phrases (c("ab","pq","xy"), list(c("ab","pq"),c("pq","xy")))

复制代码

t = c("I","like","hot","dogs","a","lot","hot","dogs","forever")
replace_phrases <- function(vec, ph){
  while(1){
    ind = c()
    l = 0
    for(j in 1:length(ph)){
      ind1 = match(ph[[j]], vec)
      if(all(!is.na(ind1))){
        if(length(ind) == 0 || ind[1] > ind1[1]){
          ind = ind1
          l = ph[[j]]
        }
      }
    }
    if(length(ind) == 0){
      return(vec)
      break
    }else{
      vec[ind[1]] = paste(l, collapse = '_')
      vec = vec[-ind[2:length(ind)]]
    }
  }
}

replace_phrases(t, list(c("hot", "dogs")))
replace_phrases(c("ab","pq","xy"), list(c("ab","pq"),c("pq","xy")))

十分感谢

好，谢谢楼主推荐！