Generate random environmental background data

Source: R/sample_envbg.R

Generate environmental background data is a function similar to sampleRandom function of the raster package but optimized for Ecological niche modeling.

sample_envbg(
  envlayers,
  nbg,
  nprop = NULL,
  coordinates = FALSE,
  cellIDs = FALSE,
  rseed = NULL
)

Arguments

envlayers

A raster stack or brick.
nbg

Number of points for the background data
nprop

Proportion of environmental data to be sampled. Default NULL
coordinates

Logical. If TRUE cell coordinates will be retuerned
cellIDs

Logical. If TRUE cell IDs will be retuerned
rseed

Random seed number. Default NULL

Examples

if (FALSE) {
wcpath <- list.files(system.file("extdata/bios",
                                 package = "ntbox"),
                     pattern = ".tif$",
                     full.names = TRUE)

envlayers <- raster::stack(wcpath)
vals <- sample_envbg(envlayers,nbg = 3583)
# Using a proportion of data
vals <- sample_envbg(envlayers,nprop = 0.20)
}