r - 在列中查找值返回 TRUE/FALSE

Question

如果这是我的代码:

df<-data.frame(speaker=c("nancyball","nancyball","wigglet","wigglet"),
               phrase=c("the cat is on the hat",
                        "the cat runs",
                        "the cat is under the bowl",
                        "a cat plays"))

prep.list<-c("on","under","in")

我想将一个新列 (df$kind) 添加到 df，其值为 T 或 F 来自 prep.list 的单词在 df$phrase 中。

必须有一个简单的方法来做到这一点。

更好的是，我希望 df$kind 返回一些不同的东西，就像我还有:

verb.list<-c("plays","sings","sits")

我会得到:

"prep, F, prep, verb"

我试过:where() 不会将我的列强制转换为向量，并且apply() 与 grep() 但它丢失了一个维度

Answer 1

你可以试试:

  df$kind <- grepl(paste(prep.list, collapse="|"), df$phrase)
  df
  #   speaker                    phrase  kind
  #1 nancyball     the cat is on the hat  TRUE
  #2 nancyball              the cat runs FALSE
  #3   wigglet the cat is under the bowl  TRUE
  #4   wigglet               a cat plays FALSE


 indx1 <- grepl(paste(prep.list, collapse="|"), df$phrase)
 indx2 <- grepl(paste(verb.list, collapse="|"), df$phrase)
 

找到@Jaap 的答案后，我猜你想要:

  df$kind <- c("F", "prep", "verb")[as.numeric(factor(1*indx1+2*indx2))] #updated based on comments from @alexis_laz
  df
  #  speaker                    phrase kind
 #1 nancyball     the cat is on the hat prep
 #2 nancyball              the cat runs    F
 #3   wigglet the cat is under the bowl prep
 #4   wigglet               a cat plays verb

更新

假设您有多个列表，并且不止一个列表匹配df$phrase的特定元素，一种方法是:

 new.list <- c("hat", "bowl", "howl")
 nm1 <- ls(pattern=".list")
 lst1 <- mget(nm1)
 indx2 <- sapply(names(lst1), function(x) {x1 <- gsub("\\..*", "", x)
                                indx <- grepl(paste(lst1[[x]], collapse="|"), df$phrase)
                                      c(NA, x1)[indx+1]})

   df$kind <- ifelse(rowSums(is.na(indx2))==ncol(indx2), "F", 
                apply(indx2, 1, function(x) paste(x[!is.na(x)], collapse="_")))

   df
   #   speaker                    phrase     kind
   #1 nancyball     the cat is on the hat new_prep
   #2 nancyball              the cat runs        F
   #3   wigglet the cat is under the bowl new_prep
   #4   wigglet               a cat plays     verb