Using the relocate function with lapply

Question

I have 4 data frames that I created to be a list

dfs <- list(bio_w, bio_k, demo_w, demo_k)

Now what I want to do is move my id column to the very front. I spent hours trying to get it to apply to all 4 dfs using the apply function but I just got error after error so i did it 1 by 1 using:

bio_w <- bio_w %>% relocate(id, .before = 1)
bio_k <- bio_w %>% relocate(id, .before = 1)
demo_w <- demo_w %>% relocate(id, .before = 1)
demo_k <- demo_k %>% relocate(id, .before = 1)

I was trying things like:

dfs2 <- lapply(dfs, FUN = function(x){x[relocate(id, .before = 1)]})

dfs2 <- lapply(dfs %>% relocate(id, .after = 0))

dfs2 <- lapply(dfs, function(x) relocate(id, .after = 0))

but I am getting different errors constantly, including:

Error in UseMethod("relocate") : 
  no applicable method for 'relocate' applied to an object of class "function"

Error in UseMethod("relocate") : 
  no applicable method for 'relocate' applied to an object of class "character"

and

Error in lapply(dfs %>% relocate(id, .after = 0)) : 
  argument "FUN" is missing, with no default

I would greatly appreciate any advice to help me learn to better understand how to use lapply properly.

Thanks

Answer 1

Your question was solved by @JilberUrbina's answer.

But, since dplyr::relocate and magrittr::'%>%' are tidyverse functions, here's an alternative with apply's equivalent, purrr::map, and the recent anonymous function's syntax \(x):
(Toy data aux_before at the end)

library(tidyverse)

# ----------------
aux_after <- map(aux_before, \(x) relocate(x, id, .before = 1))

Output:

# Output
> aux_after
[[1]]
# A tibble: 1 × 3
     id name         homeworld
  <int> <chr>        <chr>    
1    31 Qui-Gon Jinn NA       

[[2]]
# A tibble: 1 × 3
     id name    homeworld
  <int> <chr>   <chr>    
1    79 Tarfful Kashyyyk 

[[3]]
# A tibble: 1 × 3
     id name         homeworld
  <int> <chr>        <chr>    
1    51 Ki-Adi-Mundi Cerea    

[[4]]
# A tibble: 1 × 3
     id name     homeworld
  <int> <chr>    <chr>    
1    14 Han Solo Corellia

Toy data:

# Toy data
set.seed(123)

aux_before <- starwars %>% 
  select(name, homeworld) %>% 
  mutate(id = consecutive_id(name))

aux_before <- map(1:4, \(x) slice_sample(aux_before, n = 1))

> aux_before
[[1]]
# A tibble: 1 × 3
  name         homeworld    id
  <chr>        <chr>     <int>
1 Qui-Gon Jinn NA           31

[[2]]
# A tibble: 1 × 3
  name    homeworld    id
  <chr>   <chr>     <int>
1 Tarfful Kashyyyk     79

[[3]]
# A tibble: 1 × 3
  name         homeworld    id
  <chr>        <chr>     <int>
1 Ki-Adi-Mundi Cerea        51

[[4]]
# A tibble: 1 × 3
  name     homeworld    id
  <chr>    <chr>     <int>
1 Han Solo Corellia     14