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 simple 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.

### 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 single expression quoted with `funs()` or within a quosure, a string naming a function, or a function.
`...` | Additional arguments for the function calls in `.funs`. These are evaluated only once, with explicit splicing.
`.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()`, or a character vector of column names, or a numeric vector of column positions.

### Examples

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

    # Selection drops unselected variables:
    is_whole <- function(x) all(floor(x) == x)
    select_if(mtcars, is_whole, toupper)

    # But renaming retains them:
    rename_if(mtcars, is_whole, toupper)

    # The renaming function is optional for selection:
    select_if(mtcars, is_whole)

[Package dplyr version 0.7.0 Index]