Samples in 2D at resolution of raster
mSampling2D(occs, rasterTemplate, mShp, verbose = TRUE)A dataframe with at least two columns named "longitude" and "latitude", or that can be coerced into this format.
A SpatRaster object to serve
as a template for generating background sampling
coordinates.
A shapefile defining the area from which background points should be sampled.
logical. Switching to FALSE mutes message describing
which columns in occs are interpreted as x and y coordinates.
A data.frame with 2D coordinates of points
for background sampling.
This function is designed to sample background points
for distributional modeling in two dimensions. The returned
data.frame contains all points from across the designated
background. It is up to the user to determine how to
appropriately sample from those background points.
library(terra)
# Create sample raster
r <- rast(ncol=10, nrow=10)
values(r) <- 1:100
# Create test occurrences
set.seed(0)
longitude <- sample(ext(r)[1]:ext(r)[2],
size = 10, replace = FALSE)
set.seed(0)
latitude <- sample(ext(r)[3]:ext(r)[4],
size = 10, replace = FALSE)
occurrences <- data.frame(longitude,latitude)
# Generate background sampling buffer
buffPts <- vect(occurrences,
c("longitude", "latitude"))
crs(buffPts) <- crs(r)
mShp <- aggregate(buffer(buffPts, width = 1000000))
# Here's the function
result <- mSampling2D(occs = occurrences, rasterTemplate = r, mShp = mShp)
#> Using longitude and latitude
#> as x and y coordinates, respectively.