select_all {dplyr} | R Documentation

## Select and rename a selection of variables

### Description

These scoped variants of `select()` and `rename()` operate on a selection of variables. The semantics of these verbs have subtle but important differences:

- Selection drops variables that are not in the selection while renaming retains them.

- The renaming function is optional for selection but not for renaming.

The `_if` and `_at` variants always retain grouping variables for grouped data frames.

### Usage

    select_all(.tbl, .funs = list(), ...)

    rename_all(.tbl, .funs = list(), ...)

    select_if(.tbl, .predicate, .funs = list(), ...)

    rename_if(.tbl, .predicate, .funs = list(), ...)

    select_at(.tbl, .vars, .funs = list(), ...)

    rename_at(.tbl, .vars, .funs = list(), ...)

### Arguments

`.tbl` | A `tbl` object.
`.funs` | A function `fun`, a purrr style lambda `~ fun(.)` or a list of either form.
`...` | Additional arguments for the function calls in `.funs`. These are evaluated only once, with tidy dots support.
`.predicate` | A predicate function to be applied to the columns or a logical vector. The variables for which `.predicate` is or returns `TRUE` are selected. This argument is passed to `rlang::as_function()` and thus supports quosure-style lambda functions and strings representing function names.
`.vars` | A list of columns generated by `vars()`, a character vector of column names, a numeric vector of column positions, or `NULL`.

### Grouping variables

Existing grouping variables are always kept in the data frame, even if not included in the selection.

### Examples

    # Supply a renaming function:
    select_all(mtcars, toupper)
    select_all(mtcars, "toupper")
    select_all(mtcars, list(~toupper(.)))

    # Selection drops unselected variables:
    is_whole <- function(x) all(floor(x) == x)
    select_if(mtcars, is_whole, toupper)
    select_at(mtcars, vars(-contains("ar"), starts_with("c")), toupper)

    # But renaming retains them:
    rename_if(mtcars, is_whole, toupper)
    rename_at(mtcars, vars(-(1:3)), toupper)
    rename_all(mtcars, toupper)

    # The renaming function is optional for selection:
    select_if(mtcars, is_whole)
    select_at(mtcars, vars(-everything()))
    select_all(mtcars)

[Package dplyr version 0.8.0.1 Index]