Convert value labels into factor levels
labels_to_levels(x, ...)# S3 method for factor
labels_to_levels(x, verbose = TRUE, ...)
# S3 method for data.frame
labels_to_levels(
x,
select = NULL,
exclude = NULL,
ignore_case = FALSE,
append = FALSE,
regex = FALSE,
verbose = TRUE,
...
)
x
, where for all factors former levels are replaced by their value
labels.
A data frame or factor. Other variable types (e.g. numerics) are not allowed.
Currently not used.
Toggle warnings.
Variables that will be included when performing the required tasks. Can be either
a variable specified as a literal variable name (e.g., column_name
),
a string with the variable name (e.g., "column_name"
), or a character
vector of variable names (e.g., c("col1", "col2", "col3")
),
a formula with variable names (e.g., ~column_1 + column_2
),
a vector of positive integers, giving the positions counting from the left
(e.g. 1
or c(1, 3, 5)
),
a vector of negative integers, giving the positions counting from the
right (e.g., -1
or -1:-3
),
one of the following select-helpers: starts_with()
, ends_with()
,
contains()
, a range using :
or regex("")
. starts_with()
,
ends_with()
, and contains()
accept several patterns, e.g
starts_with("Sep", "Petal")
.
or a function testing for logical conditions, e.g. is.numeric()
(or
is.numeric
), or any user-defined function that selects the variables
for which the function returns TRUE
(like: foo <- function(x) mean(x) > 3
),
ranges specified via literal variable names, select-helpers (except
regex()
) and (user-defined) functions can be negated, i.e. return
non-matching elements, when prefixed with a -
, e.g. -ends_with("")
,
-is.numeric
or -(Sepal.Width:Petal.Length)
. Note: Negation means
that matches are excluded, and thus, the exclude
argument can be
used alternatively. For instance, select=-ends_with("Length")
(with
-
) is equivalent to exclude=ends_with("Length")
(no -
). In case
negation should not work as expected, use the exclude
argument instead.
If NULL
, selects all columns. Patterns that found no matches are silently
ignored, e.g. extract_column_names(iris, select = c("Species", "Test"))
will just return "Species"
.
See select
, however, column names matched by the pattern
from exclude
will be excluded instead of selected. If NULL
(the default),
excludes no columns.
Logical, if TRUE
and when one of the select-helpers or
a regular expression is used in select
, ignores lower/upper case in the
search pattern when matching against variable names.
Logical or string. If TRUE
, recoded or converted variables
get new column names and are appended (column bind) to x
, thus returning
both the original and the recoded variables. The new columns get a suffix,
based on the calling function: "_r"
for recode functions, "_n"
for
to_numeric()
, "_f"
for to_factor()
, or "_s"
for
slide()
. If append=FALSE
, original variables in x
will be
overwritten by their recoded versions. If a character value, recoded
variables are appended with new column names (using the defined suffix) to
the original data frame.
Logical, if TRUE
, the search pattern from select
will be
treated as regular expression. When regex = TRUE
, select must be a
character string (or a variable containing a character string) and is not
allowed to be one of the supported select-helpers or a character vector
of length > 1. regex = TRUE
is comparable to using one of the two
select-helpers, select = contains("")
or select = regex("")
, however,
since the select-helpers may not work when called from inside other
functions (see 'Details'), this argument may be used as workaround.
labels_to_levels()
allows to use value labels of factors as their levels.
data(efc)
# create factor
x <- as.factor(efc$c172code)
# add value labels - these are not factor levels yet
x <- assign_labels(x, values = c(`1` = "low", `2` = "mid", `3` = "high"))
levels(x)
data_tabulate(x)
x <- labels_to_levels(x)
levels(x)
data_tabulate(x)
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