How to name objects in many lists at once in R?-CodePudding

I've got three lists with and each of them contains many tibbles. I want to name objects within the lists based on a particular value in the tibble. I know how to do it with one list at a time. To make things easier, I'll use vectors in my example:

library("purrr")

list1 <- list(c(id = "ABC", val=1), c(id = "DEF", val = 2), c(id = "GHI", val = 3))
list2 <- list(c(id = "JKL", val=4), c(id = "MNO", val = 5), c(id = "PRS", val = 6))
list3 <- list(c(id = "TUW", val=7), c(id = "XYZ", val = 8), c(id = "ZYX", val = 8))

names(list1) <- map_chr(list1, ~ .x[["id"]])
names(list2) <- map_chr(list2, ~ .x[["id"]])
names(list3) <- map_chr(list3, ~ .x[["id"]])

It works but I wonder if there's any bulk method of getting it done. I've tried using a for loop, but it didn't work, it creates separate i variable but doesn't rename objects in my lists:

for (i in c(list1, list2, list3)) {names(i) <- map_chr(i, ~ .x[["id"]])}

I know for loops are considered a bad practice in R so other suggestions would be much appreciated.

CodePudding user response：

One way to approach this is to combine your lists first, so that the combined lists will have their names changed

list_of_lists <- list(list1, list2, list3)

list_of_lists <- 
  lapply(list_of_lists, function(y) setNames(y, map_chr(y, ~ .x[["id"]])))

[[1]]
[[1]]$ABC
   id   val 
"ABC"   "1" 

[[1]]$DEF
   id   val 
"DEF"   "2" 

[[1]]$GHI
   id   val 
"GHI"   "3" 


[[2]]
[[2]]$JKL
   id   val 
"JKL"   "4" 

[[2]]$MNO
   id   val 
"MNO"   "5" 

[[2]]$PRS
   id   val 
"PRS"   "6" 


[[3]]
[[3]]$TUW
   id   val 
"TUW"   "7" 

[[3]]$XYZ
   id   val 
"XYZ"   "8" 

[[3]]$ZYX
   id   val 
"ZYX"   "8"

CodePudding user response：

In the for loop, we may need assign

for(nm in paste0('list', 1:3)) {
    tmp <- get(nm)
    names(tmp) <- sapply(tmp, function(x) x[["id"]])
     assign(nm, tmp)
}

-output

> list1
$ABC
   id   val 
"ABC"   "1" 

$DEF
   id   val 
"DEF"   "2" 

$GHI
   id   val 
"GHI"   "3"