Prepare continuous color scale limits with quantile/cutoff controls

Computes the lower and upper cutoffs for a continuous color/fill scale, applies data winsorization (clamping), and returns the results needed by scale_fill_gradientn or scale_color_gradientn.

Usage

prepare_continuous_color_scale(
  data,
  column,
  lower_quantile = 0,
  upper_quantile = 0.99,
  lower_cutoff = NULL,
  upper_cutoff = NULL,
  bg_cutoff = NULL
)

Arguments

data

A data frame.

column

The column name in data to use for the color scale.

lower_quantile, upper_quantile

Lower and upper quantiles for the continuous color/fill scale. The actual cutoffs are determined by these quantiles when lower_cutoff and upper_cutoff are NULL. Defaults: lower_quantile = 0, upper_quantile = 0.99.

lower_cutoff, upper_cutoff

Explicit lower and upper cutoffs for the continuous color/fill scale. When NULL (the default), the cutoffs are determined by lower_quantile and upper_quantile via quantile. Values outside the [lower_cutoff, upper_cutoff] range are clamped (winsorized) to the nearest cutoff value.

bg_cutoff

Optional numeric cutoff — values <= bg_cutoff are set to NA before computing cutoffs. Default is NULL.

Value

A list with components:

data

The modified data frame (with winsorized column).

feat_colors_value

Numeric vector of 100 evenly-spaced values from lower_cutoff to upper_cutoff.

limits

Numeric vector of length 2 giving the range c(lower_cutoff, upper_cutoff).