REDCapCAST/reference/as_factor.md

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# Convert labelled vectors to factors while preserving attributes
This extends
[as_factor](https://forcats.tidyverse.org/reference/as_factor.html) as
well as
[as_factor](https://forcats.tidyverse.org/reference/as_factor.html), by
appending original attributes except for "class" after converting to
factor to avoid ta loss in case of rich formatted and labelled data.
## Usage
``` r
as_factor(x, ...)
# S3 method for class 'factor'
as_factor(x, ...)
# S3 method for class 'logical'
as_factor(x, ...)
# S3 method for class 'numeric'
as_factor(x, ...)
# S3 method for class 'character'
as_factor(x, ...)
# S3 method for class 'haven_labelled'
as_factor(
x,
levels = c("default", "labels", "values", "both"),
ordered = FALSE,
...
)
# S3 method for class 'labelled'
as_factor(
x,
levels = c("default", "labels", "values", "both"),
ordered = FALSE,
...
)
# S3 method for class 'data.frame'
as_factor(x, ..., only_labelled = TRUE)
```
## Arguments
- x:
Object to coerce to a factor.
- ...:
Other arguments passed down to method.
- levels:
How to create the levels of the generated factor:
\* "default": uses labels where available, otherwise the values.
Labels are sorted by value. \* "both": like "default", but pastes
together the level and value \* "label": use only the labels;
unlabelled values become \`NA\` \* "values": use only the values
- ordered:
If \`TRUE\` create an ordered (ordinal) factor, if \`FALSE\` (the
default) create a regular (nominal) factor.
- only_labelled:
Only apply to labelled columns?
## Details
Please refer to parent functions for extended documentation. To avoid
redundancy calls and errors, functions are copy-pasted here
Empty variables with empty levels attribute are interpreted as logicals
## Examples
``` r
# will preserve all attributes
c(1, 4, 3, "A", 7, 8, 1) |> as_factor()
#> [1] 1 4 3 A 7 8 1
#> Levels: 1 4 3 A 7 8
structure(c(1, 2, 3, 2, 10, 9),
labels = c(Unknown = 9, Refused = 10)
) |>
as_factor() |>
dput()
#> structure(c(1L, 2L, 3L, 2L, 5L, 4L), levels = c("1", "2", "3",
#> "9", "10"), class = "factor", labels = c(Unknown = 9, Refused = 10
#> ))
structure(c(1, 2, 3, 2, 10, 9),
labels = c(Unknown = 9, Refused = 10),
class = "haven_labelled"
) |>
as_factor() |> class()
#> [1] "factor"
structure(rep(NA,10),
class = c("labelled")
) |>
as_factor() |> summary()
#> FALSE TRUE NA's
#> 0 0 10
rep(NA,10) |> as_factor()
#> [1] <NA> <NA> <NA> <NA> <NA> <NA> <NA> <NA> <NA> <NA>
#> Levels: FALSE TRUE
```