Given the coordinates, the species' name and the environmental variables, the function creates an SWD object (sample with data).
prepareSWD(
species,
env,
p = NULL,
a = NULL,
categorical = NULL,
verbose = TRUE
)
An SWD object.
character. The name of the species.
rast containing the environmental variables used to extract the values at coordinate locations.
data.frame. The coordinates of the presence locations.
data.frame. The coordinates of the absence/background locations.
vector indicating which of the environmental variable are categorical.
logical, if TRUE
prints informative messages.
Sergio Vignali
The SWD object is created in a way that the presence locations are always before than the absence/background locations.
# Acquire environmental variables
files <- list.files(path = file.path(system.file(package = "dismo"), "ex"),
pattern = "grd",
full.names = TRUE)
predictors <- terra::rast(files)
# Prepare presence and background locations
p_coords <- virtualSp$presence
bg_coords <- virtualSp$background
# Create the SWD object
data <- prepareSWD(species = "Virtual species",
p = p_coords,
a = bg_coords,
env = predictors,
categorical = "biome")
data
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