select_helpers {dplyr} | R Documentation |
These functions allow you to select variables based on their names.
starts_with()
: starts with a prefix
ends_with()
: ends with a prefix
contains()
: contains a literal string
matches()
: matches a regular expression
num_range()
: a numerical range like x01, x02, x03.
one_of()
: variables in character vector.
everything()
: all variables.
current_vars() starts_with(match, ignore.case = TRUE, vars = current_vars()) ends_with(match, ignore.case = TRUE, vars = current_vars()) contains(match, ignore.case = TRUE, vars = current_vars()) matches(match, ignore.case = TRUE, vars = current_vars()) num_range(prefix, range, width = NULL, vars = current_vars()) one_of(..., vars = current_vars()) everything(vars = current_vars())
match |
A string. |
ignore.case |
If |
vars |
A character vector of variable names. When called from inside
|
prefix |
A prefix that starts the numeric range. |
range |
A sequence of integers, like |
width |
Optionally, the "width" of the numeric range. For example, a range of 2 gives "01", a range of three "001", etc. |
... |
One or more character vectors. |
An integer vector given the position of the matched variables.
iris <- tbl_df(iris) # so it prints a little nicer select(iris, starts_with("Petal")) select(iris, ends_with("Width")) select(iris, contains("etal")) select(iris, matches(".t.")) select(iris, Petal.Length, Petal.Width) select(iris, everything()) vars <- c("Petal.Length", "Petal.Width") select(iris, one_of(vars))