Learn R Programming

dplyr (version 0.7.2)

select_all: 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

Run this code
# NOT RUN {
# 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)
# }

Run the code above in your browser using DataLab