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Spread list column into new columns

Source: R/other_functions.R
spread_list.Rd

Spread an existing list column into new columns on a data.frame. Note that every element on every observation must have a name for the function to do its work. Original column will be automatically suppressed but you can set the replace argument to avoid it.

Usage

spread_list(df, col, str = NULL, replace = TRUE)

Arguments

df

Dataframe

col

Variable name.

str

Character. Start column names with. If set to NULL, original name of column will be used.

replace

Boolean. Replace original values (delete column)

Value

data.frame. Result of un-nesting named or un-named list columns.

Examples

df <- dplyr::starwars
# Un-named list columns
spread_list(df, films, replace = FALSE) %>%
  dplyr::select(name, dplyr::starts_with("films")) %>%
  head(8)
#> # A tibble: 8 × 9
#>   name    films `films_A New Hope` films_Attack of the …¹ films_Return of the …²
#>   <chr>   <lis> <lgl>              <lgl>                  <lgl>                 
#> 1 Luke S… <chr> TRUE               FALSE                  TRUE                  
#> 2 C-3PO   <chr> TRUE               TRUE                   TRUE                  
#> 3 R2-D2   <chr> TRUE               TRUE                   TRUE                  
#> 4 Darth … <chr> TRUE               FALSE                  TRUE                  
#> 5 Leia O… <chr> TRUE               FALSE                  TRUE                  
#> 6 Owen L… <chr> TRUE               TRUE                   FALSE                 
#> 7 Beru W… <chr> TRUE               TRUE                   FALSE                 
#> 8 R5-D4   <chr> TRUE               FALSE                  FALSE                 
#> # ℹ abbreviated names: ¹​`films_Attack of the Clones`,
#> #   ²​`films_Return of the Jedi`
#> # ℹ 4 more variables: `films_Revenge of the Sith` <lgl>,
#> #   `films_The Empire Strikes Back` <lgl>, `films_The Force Awakens` <lgl>,
#> #   `films_The Phantom Menace` <lgl>
# Named (and un-nammed) list columns
df <- dplyr::tibble(id = 1:3, platform = list(
  list("fb" = 1, "ig" = 2),
  list("fb" = 3),
  list()
))
spread_list(df, platform, str = "ptf_")
#> # A tibble: 3 × 3
#>      id ptf_fb ptf_ig
#>   <int>  <dbl>  <dbl>
#> 1     1      1      2
#> 2     2      3      0
#> 3     3     NA     NA