selectBackgroundPoints: Randomly select background points for a given extent.

In jscavetta95/maxentools: Species Distribution Modeling with Maxent

Description

If provided, background points can be selected from a probablity density layer, such as a bias file. Otherwise, background points are uniformly selected across the layer extent. Selected background points will be paired with environmental data for each environmental predictor provided.

Usage

selectBackgroundPoints(sample_layer, occurrence_data_list, predictors,
  categoricals, num_background_points, use_probabilty, shape,
  output_folder)

Arguments

sample_layer	A layer with the extent from which to randomly select background points.
occurrence_data_list	A list of occurrence point dataframes for each species sampled. Only required for plotting.
predictors	A RasterStack of RasterLayer objects representing the environmental predictors.
categoricals	A vector of indecies specifying the environmental predictors that contain catagorical or discrete data.
num_background_points	The number of background points to select.
shape	A shapefile to overlay on the plotted data points map.
output_folder	Location to save data and plots.
use_probablity	Set TRUE if the background points should be sampled using the bias probablity density. FALSE for uniform sampling.

Value

Dataframe of selected background coordinates and extracted environmental predictor data.

jscavetta95/maxentools documentation built on Dec. 8, 2019, 1:26 p.m.