delimit: Delimit study area and background coordinates

In mopa: Species Distribution MOdeling with Pseudo-Absences

Description

Creation of polygon shapes from bounding coordinates and delimitation of SpatialPoints data to the defined boundaries. This is an internal function used by function backgroundGrid.

Usage

delimit(bounding.coords, grid, names = NULL)

Arguments

bounding.coords	A vector or a list of vectors with bounding coordinates in the following form: c(x1, x2, y1, y2). Also object returned by function boundingCoords.
grid	SpatialPoints object
names	Character. Names or IDs to be given to each shape. If not specified names of the object passed to bounding.coords will be given. In case this object has no names the background numbers will be used as names.

Details

This function is aimed at restricting the study area inside the bounding boxes of a group of points (presences). The study area can be represented as a SpatialPoints object of a regular point grid, this grid also represents the background (excluding presences) from which pseudo-absences can be sampled. Ideally, this grid is extracted from the raster objects of the variables (centroids) to be used for modelling, see xyFromCell, extract and example below. bbs.grid is the background inside bbs shapes.

Value

A list with two components:

• polygonsSpatialPolygons of the bounding boxes

• xylist(s) of matrix(ces) of the background xy coordinates in columns.

Author(s)

M. Iturbide

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.

mopa documentation built on May 2, 2019, 6:47 a.m.