mopa (version 1.0.1)

backgroundGrid: Create background coordinates from raster object

Description

Creates the background coordinates used for defining the study area and for generating pseudo-absences.

Usage

backgroundGrid(raster, spatial.subset = NULL)

Arguments

raster

Raster object with projection (?raster::projection and ?crs) from which to extract the the point grid (used as background coordinates for generating pseudo-absences)

spatial.subset

Object of class extent (see extent) or a two column data.frame (or matrix) of coordinates (xy, each row is a point).

Value

A list with a SpatialPolygons object and a matrix of the background coordinates

Details

If a data.frame, matrix or a list of the previous is passed to spatial.subset the bounding coordinates are extracted to delimit the background. For example, to bound the study area to the spatial distribution of a species.

References

Iturbide, M., Bedia, J., Herrera, S., del Hierro, O., Pinto, M., Gutierrez, J.M., 2015. A framework for species distribution modelling with improved pseudo-absence generation. Ecological Modelling. DOI:10.1016/j.ecolmodel.2015.05.018.

Examples

# NOT RUN {
## Load presences
data(Oak_phylo2)

## Load rasters
destfile <- tempfile()
data.url <- "https://raw.githubusercontent.com/SantanderMetGroup/mopa/master/data/biostack.rda"
download.file(data.url, destfile)
load(destfile, verbose = TRUE)

projection(biostack$baseline) <- CRS("+proj=longlat +init=epsg:4326")
r <- biostack$baseline[[1]]

## Background around a set of coordinates
bg.species <- backgroundGrid(r, Oak_phylo2)
## Background of a subdomain of the study area
bg.subdomain <- backgroundGrid(r, extent(c(-10, 30, 35, 65)))
## Background of the whole study area
bg <- backgroundGrid(r)

# plot(bg$xy)
# plot(bg.subdomain$xy)
# plot(bg.species$xy$H11)
plot(bg.species$xy$H01)

# }