Convert Peaks to Tidy Table

step_measure_peaks_to_table() creates a specification of a recipe step that converts the peaks list-column to a wide format with one column per peak property.

Usage

step_measure_peaks_to_table(
  recipe,
  prefix = "peak_",
  properties = c("location", "height", "area"),
  max_peaks = 10,
  role = NA,
  trained = FALSE,
  skip = FALSE,
  id = recipes::rand_id("measure_peaks_to_table")
)

Arguments

recipe

A recipe object.

prefix

Prefix for generated column names. Default is "peak_".

properties

Which peak properties to include. Default includes location, height, and area for each peak.

max_peaks

Maximum number of peaks to include in output. If a sample has more peaks, only the first max_peaks are included.

role

Not used.

trained

Logical indicating if the step has been trained.

skip

Logical. Should the step be skipped when baking?

id

Unique step identifier.

Value

An updated recipe with the new step added.

Details

This step converts peak data to a wide format suitable for modeling. For each peak, it creates columns like peak_1_location, peak_1_height, peak_1_area, etc.

The .peaks and .measures columns are removed after conversion.

See also

Other peak-operations: step_measure_peaks_deconvolve(), step_measure_peaks_detect(), step_measure_peaks_filter(), step_measure_peaks_integrate()

Examples

library(recipes)

rec <- recipe(water + fat + protein ~ ., data = meats_long) |>
  update_role(id, new_role = "id") |>
  step_measure_input_long(transmittance, location = vars(channel)) |>
  step_measure_peaks_detect(min_height = 0.5) |>
  step_measure_peaks_integrate() |>
  step_measure_peaks_to_table(max_peaks = 5) |>
  prep()

result <- bake(rec, new_data = NULL)