删除向量中属于另一个向量子串的元素

Question

有没有更好的方法来实现这个目标？我想从此向量中删除所有字符串，它们是其他元素的子字符串。

words = c("please can you", 
  "please can", 
  "can you", 
  "how did you", 
  "did you",
  "have you")
> words
[1] "please can you" "please can"     "can you"        "how did you"    "did you"        "have you"

library(data.table)
library(stringr)
dt = setDT(expand.grid(word1 = words, word2 = words, stringsAsFactors = FALSE))
dt[, found := str_detect(word1, word2)]
setdiff(words, dt[found == TRUE & word1 != word2, word2])
[1] "please can you" "how did you"    "have you" 

这可行，但似乎有点矫枉过正，我有兴趣知道一种更优雅的方法。

Answer 1

搜索 words 中 words 的每个组成部分，保留出现过一次的内容:

words[colSums(sapply(words, grepl, words, fixed = TRUE)) == 1]

给予:

[1] "please can you" "how did you"    "have you"