how to name the element list automatically in R (based on the number of the elements)

Question

I have a list of elements where the number of elements is not fixed. I would like to name the element automatically based on their number. For example, if the list contains 9, then I would like to give names for the nine elements, as Model_1, Model_2, and so on. If the number of the element is changed, then, I do not need to change it manually.

For example, in the following code, the name of the elements must be done manually.

names1 <- c("1","2", "3", "4", "5", "6", "7", "8", "9")

lapply(setNames(unlist(myres), paste0(names1, '_Model')), function(x) 
  setNames(x, paste0('Res_', seq_along(x))))

Is there an automatic way to set the names of the elements which are not fixed?

It's not clear to me what you're input and what's your desired output, but if your list is `myres`, then you can do `setNames(myres, paste0("Model_", seq_along(myres))`. It's easier to help you if you include a simple [reproducible example](https://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example) with sample input and desired output that can be used to test and verify possible solutions. — MrFlick, Jun 06 '21 at 06:40

score 1 · Answer 1 · answered Jun 06 '21 at 07:03

1

Something like this?

names(myres) <- paste0("Model_", 1:length(myres))

or

setNames(myres, paste0("Model_", 1:length(myres)))

answered Jun 06 '21 at 07:03

Manuel Popp

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jpdugo17 · Accepted Answer · 2021-06-06T07:09:35.350

library(purrr)
the_list <- map(1:5, ~.x)

names <- paste0('result', as.character(seq(1, length(the_list))))
purrr::set_names(the_list, names)
#> $result1
#> [1] 1
#> 
#> $result2
#> [1] 2
#> 
#> $result3
#> [1] 3
#> 
#> $result4
#> [1] 4
#> 
#> $result5
#> [1] 5

more_names <- 
    map(1:5, ~ rep(1, .x)) %>% 
    map(~length(.x)) %>% 
    map(~paste0('result', as.character(seq(1, .x))) )


map(1:5, ~ vector('list', .x)) %>% 
    map2(more_names, ~ set_names(.x, .y))
#> [[1]]
#> [[1]]$result1
#> NULL
#> 
#> 
#> [[2]]
#> [[2]]$result1
#> NULL
#> 
#> [[2]]$result2
#> NULL
#> 
#> 
#> [[3]]
#> [[3]]$result1
#> NULL
#> 
#> [[3]]$result2
#> NULL
#> 
#> [[3]]$result3
#> NULL
#> 
#> 
#> [[4]]
#> [[4]]$result1
#> NULL
#> 
#> [[4]]$result2
#> NULL
#> 
#> [[4]]$result3
#> NULL
#> 
#> [[4]]$result4
#> NULL
#> 
#> 
#> [[5]]
#> [[5]]$result1
#> NULL
#> 
#> [[5]]$result2
#> NULL
#> 
#> [[5]]$result3
#> NULL
#> 
#> [[5]]$result4
#> NULL
#> 
#> [[5]]$result5
#> NULL

^{Created on 2021-06-06 by the reprex package (v2.0.0)}

how to name the element list automatically in R (based on the number of the elements)

2 Answers2