Add raster data to tracking data — atl_add_raster

This function extracts raster data (for example bathymetry data) at specified coordinates and adds it as a column to the input data.table.

Usage

atl_add_raster_data(
  data = NULL,
  x = "x",
  y = "y",
  projection = sf::st_crs(32631),
  raster_data,
  var_name = NULL,
  new_name = NULL,
  change_unit = 1
)

Arguments

data: A data.table containing the data to which raster values will be added. If not a data.table, it will be coerced to one.
x: Character string specifying the column name for x-coordinates. Defaults to "x".
y: Character string specifying the column name for y-coordinates. Defaults to "y".
projection: A coordinate reference system (CRS) for the spatial data in the input. Defaults to EPSG:32631.
raster_data: A SpatRaster object from which values will be extracted.
var_name: Character string specifying the raster variable to extract. Defaults to the first layer if NULL.
new_name: Character string specifying the name of the new column in the output. If NULL, uses var_name.
change_unit: Numeric value by which to multiply extracted raster values #' before adding them to the data. Defaults to 1.

Value

A data.table with the extracted raster data added as a new column.