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Reorder the levels of a categorical column

Source: R/level_order.R
apply_level_order.Rd

Re-levels data[[column]] as a factor whose levels follow order, which is how the plot modules set the order of a categorical axis: the plot functions, the statistics and their brackets all take the axis order from the column's levels, so they stay in step.

Usage

apply_level_order(data, column, order)

Arguments

data

A data frame.

column

The name of the column.

order

Character vector of levels in the order wanted, e.g. the value of a level_order_input(). Merged as in level_order_choices(), with no cap on the number of levels.

Value

data, with column re-levelled. It is returned unchanged when order is empty or already the default order, or column is missing or numeric.

See also

level_order_input(), level_order_choices(), setup_level_order()

Author

Jared Andrews

Examples

df <- apply_level_order(example_iris, "Species", c("virginica", "setosa"))
levels(df$Species)
#> [1] "virginica"  "setosa"     "versicolor"