Convert input to a factor.

The base function as.factor() is not a generic, but this variant is. Methods are provided for factors, character vectors, labelled vectors, and data frames. By default, when applied to a data frame, it only affects labelled columns.

# S3 method for data.frame
as_factor(x, ..., only_labelled = TRUE)

# S3 method for haven_labelled
as_factor(
  x,
  levels = c("default", "labels", "values", "both"),
  ordered = FALSE,
  ...
)

# S3 method for labelled
as_factor(
  x,
  levels = c("default", "labels", "values", "both"),
  ordered = FALSE,
  ...
)

Arguments

x	Object to coerce to a factor.
...	Other arguments passed down to method.
only_labelled	Only apply to labelled columns?
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.

Details

Includes methods for both class haven_labelled and labelled for backward compatibility.

Examples

x <- labelled(sample(5, 10, replace = TRUE), c(Bad = 1, Good = 5))

# Default method uses values where available
as_factor(x)
#>  [1] Good 4    Good 4    Bad  Good Good Good 2    3   
#> Levels: Bad 2 3 4 Good
# You can also extract just the labels
as_factor(x, levels = "labels")
#>  [1] Good <NA> Good <NA> Bad  Good Good Good <NA> <NA>
#> Levels: Bad Good
# Or just the values
as_factor(x, levels = "values")
#>  [1] 5    <NA> 5    <NA> 1    5    5    5    <NA> <NA>
#> Levels: 1 5
# Or combine value and label
as_factor(x, levels = "both")
#>  [1] [5] Good 4        [5] Good 4        [1] Bad  [5] Good [5] Good [5] Good
#>  [9] 2        3       
#> Levels: [1] Bad 2 3 4 [5] Good