检查元素是否包含在不同长度的不相等元素上

编程问答 2022-06-05

问题描述

我正在尝试查找某个字符向量的一部分是否与另一个字符向量的一部分重叠

x <- c("OCT/NOV/DEC","JAN/DEC/AUG")
y <- c("JAN/FEB/MAR","APR/MAY/JUN","JUL/AUG/SEP")

# Months should be split into separate characters

So I would use:

list_x <- strsplit(x,'/')
list_x

#> [[1]]
#> [1] "OCT" "NOV" "DEC"
#> 
#> [[2]]
#> [1] "JAN" "DEC" "AUG"

list_y <- strsplit(y,'/')
list_y

#> [[1]]
#> [1] "JAN" "FEB" "MAR"
#> 
#> [[2]]
#> [1] "APR" "MAY" "JUN"
#> 
#> [[3]]
#> [1] "JUL" "AUG" "SEP"

如我们所见，list_x [[1]]在list_y中没有任何元素，因此应返回FALSE；

list_x [[2]]具有“ JAN”和“ AUG”，它们位于list_y [[1]]和list_y [[3]]中，因此应返回TRUE 

# The response should be 

c(FALSE,TRUE) # for each of x elements

# I tried:

detect <- function(x,y){ 
  mapply(function(x,y) any(x %in% y),strsplit(x,'/'),strsplit(y,'/'))
}

detect(x,y)

# Which gives a warning stating the lengths are not multiple and:
#> [1] FALSE FALSE FALSE

那么我怎么知道y元素中是否也有x个元素？

编辑：在阿克伦（Akrun）的回应之后，我尝试了一种涉及非等额联接的更复杂方法

detect <- function(a,b){
  sapply(str_split(a,function(x) any(sapply(str_split(b,function(y) any(x %in% y))))
}

a <- tibble(a1 = c("A/B/C","F/E/G"),b1 = c(1,2),c1 = c("OCT/NOV/DEC","JAN/DEC/AUG"))

b <- tibble(a2 = c("A/B/C","D/E/F","G/H/I"),b2 = c(1,2,3),c2 = c("JAN/FEB/MAR","JUL/AUG/SEP"))

fuzzyjoin::fuzzy_left_join(a,b,by = c("a1" = "a2","b1" = "b2","c1" = "c2"),match_fun = list(detect,`==`,detect))

## Wrong Result:
#>  a1       b1 c1          a2       b2 c2         
#>  <chr> <int> <chr>       <chr> <int> <chr>      
#> 1 A/B/C     1 OCT/NOV/DEC NA       NA NA         
#> 2 F/E/G     2 JAN/DEC/AUG D/E/F     2 APR/MAY/JUN

# Row 2: Although a1 and a2 have matching characters and b1 matches b2,c1 and c2 have no matching characters,so the join shouldn't be possible

## Expected:
#>  a1       b1 c1          a2       b2 c2         
#>  <chr> <int> <chr>       <chr> <int> <chr>      
#> 1 A/B/C     1 OCT/NOV/DEC NA       NA NA         
#> 2 F/E/G     2 JAN/DEC/AUG NA       NA NA

也许我在此功能中误解了某些内容？

解决方法

我们可以将嵌套sapply与any一起使用

sapply(list_x,function(x) any(sapply(list_y,function(y) any(x %in% y))))
#[1] FALSE  TRUE

对于更新后的数据，如果我们将any更改为all，它将得到预期的输出结果

detect <- function(a,b){
   sapply(str_split(a,'/'),function(x) all(sapply(str_split(b,function(y) any(x %in% y))))
 }
 fuzzyjoin::fuzzy_left_join(a,b,by = c("a1" = "a2","b1" = "b2","c1" = "c2"),match_fun = list(detect,`==`,detect))
# A tibble: 2 x 6
#  a1       b1 c1          a2       b2 c2   
#  <chr> <dbl> <chr>       <chr> <dbl> <chr>
#1 A/B/C     1 OCT/NOV/DEC <NA>     NA <NA> 
#2 F/E/G     2 JAN/DEC/AUG <NA>     NA <NA>
applylistmapplyrrvectorvector