R: Select all variables or the last variable

everything {tidyselect} | R Documentation

## Select all variables or the last variable

### Description

These functions are selection helpers.

- `everything()` selects all variable. It is also useful in combination with other tidyselect operators.

- `last_col()` selects the last variable.

### Usage

    everything(vars = NULL)

    last_col(offset = 0L, vars = NULL)

### Arguments

`vars` | A character vector of variable names. If not supplied, the variables are taken from the current selection context (as established by functions like `select()` or `pivot_longer()`).
`offset` | Set it to `n` to select the nth var from the end.

### Examples

Selection helpers can be used in functions like `dplyr::select()` or `tidyr::pivot_longer()`. Let's first attach the tidyverse:

    library(tidyverse)

    # For better printing
    iris <- as_tibble(iris)
    mtcars <- as_tibble(mtcars)

Use `everything()` to select all variables:

    iris %>% select(everything())
    #> # A tibble: 150 x 5
    #>   Sepal.Length Sepal.Width Petal.Length Petal.Width Species
    #>          <dbl>       <dbl>        <dbl>       <dbl> <fct>
    #> 1          5.1         3.5          1.4         0.2 setosa
    #> 2          4.9         3            1.4         0.2 setosa
    #> 3          4.7         3.2          1.3         0.2 setosa
    #> 4          4.6         3.1          1.5         0.2 setosa
    #> # ... with 146 more rows

    mtcars %>% pivot_longer(everything())
    #> # A tibble: 352 x 2
    #>   name  value
    #>   <chr> <dbl>
    #> 1 mpg      21
    #> 2 cyl       6
    #> 3 disp    160
    #> 4 hp      110
    #> # ... with 348 more rows

Use `last_col()` to select the last variable:

    iris %>% select(last_col())
    #> # A tibble: 150 x 1
    #>   Species
    #>   <fct>
    #> 1 setosa
    #> 2 setosa
    #> 3 setosa
    #> 4 setosa
    #> # ... with 146 more rows

    mtcars %>% pivot_longer(last_col())
    #> # A tibble: 32 x 12
    #>     mpg   cyl  disp    hp  drat    wt  qsec    vs    am  gear name  value
    #>   <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <chr> <dbl>
    #> 1  21       6   160   110  3.9   2.62  16.5     0     1     4 carb      4
    #> 2  21       6   160   110  3.9   2.88  17.0     0     1     4 carb      4
    #> 3  22.8     4   108    93  3.85  2.32  18.6     1     1     4 carb      1
    #> 4  21.4     6   258   110  3.08  3.22  19.4     1     0     3 carb      1
    #> # ... with 28 more rows

Supply an offset `n` to select a variable located `n` positions from the end:

    mtcars %>% select(1:last_col(5))
    #> # A tibble: 32 x 6
    #>     mpg   cyl  disp    hp  drat    wt
    #>   <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
    #> 1  21       6   160   110  3.9   2.62
    #> 2  21       6   160   110  3.9   2.88
    #> 3  22.8     4   108    93  3.85  2.32
    #> 4  21.4     6   258   110  3.08  3.22
    #> # ... with 28 more rows

### See Also

The selection language page, which includes links to other selection helpers.

[Package tidyselect version 1.1.2 Index]