Define "into" using "col" when separating

[jrogol]

I'm curious if there's a way to programmatically assign the into argument of tidyr::separate based on the col argument. The data I receive (a sample is below!) often contains hyphenated columns like "GP-GS" or "sb-att".

library(tidyverse)
test <- tribble(~Player, ~"gp-gs", ~ab, ~"sb-att",
        "A", "16-16", 68, "6-9",
        "B", "10-6", 26, "0-1",
        "C", "14-9", 69, "5-9",
        )

My first thought was to create a new function separate2 and use that:

separate2 <- function(data, col, ...) {
  
  separate(data, col,
           into = c(str_extract(col, "^[^-]+"),
                    str_extract(col,"[^-]+$")),
           sep = "[-]+", 
           extra = "merge")
}

separate2(test,"gp-gs")

While this works, col must be quoted for it to work. Tidyeval may be a means to providing functionality similar to tidyr::separate, but I'm unsure where to begin.

As a bonus question: how might one apply the new separate2 function to all columns containing a hyphen (as opposed to explicitly naming the columns, which are inconsistently named across data sources)? A for loop certainly works, but is there a more "tidy" solution?

for (col in str_subset(names(test),"-")) {
  test <- separate2(test,col)
}

Thanks in advance!

[mishabalyasin]

You can do both of those things, but I'm not sure whether it improves things, to be honest

library(tidyverse)
test <- tribble(~Player, ~"gp-gs", ~ab, ~"sb-att",
                "A", "16-16", 68, "6-9",
                "B", "10-6", 26, "0-1",
                "C", "14-9", 69, "5-9",
)

separate2 <- function(data, col, ...) {
  col <- rlang::as_name(rlang::ensym(col))
  
  separate(data, col,
           into = c(str_extract(col, "^[^-]+"),
                    str_extract(col, "[^-]+$")),
           sep = "[-]+", 
           extra = "merge")
}

funs <- purrr::map(str_subset(names(test),"-"), function(col){
  purrr::partial(separate2, col = !!col)
}) 
fun <- purrr::compose(!!!funs)

fun(test)
#> # A tibble: 3 x 6
#>   Player gp    gs       ab sb    att  
#>   <chr>  <chr> <chr> <dbl> <chr> <chr>
#> 1 A      16    16       68 6     9    
#> 2 B      10    6        26 0     1    
#> 3 C      14    9        69 5     9

^{Created on 2019-03-20 by the reprex package (v0.2.1)}

[jrogol]

Misha,

Thanks for the feedback! That's working (for the time being...) on my end. I appreciate the help!

[mara]

If your question's been answered (even if by you), would you mind choosing a solution? (See FAQ below for how).

Having questions checked as resolved makes it a bit easier to navigate the site visually and see which threads still need help.

FAQ: How do I mark a solution?

If your question has been answered, don't forget to mark the solution! How do I mark a solution? Find the reply you want to mark as the solution and look for the row of small gray icons at the bottom of that reply. Click the one that looks like a box with a checkmark in it: [image] Hovering over the mark solution button shows the label, "Select if this reply solves the problem". If you don't see the mark solution button, try clicking the three dots button ( ••• ) to expand the full set of options. When a solution is chosen, the icon turns green and the hover label changes to: "Unselect if this reply no longer solves the problem". Success! [solution_reply_author] …

Thanks