species.richness.main 		The main function to estimate or cross-validate the species richness based on given species occurences.
species.richness 		Estimates the species richness based on given species occurences.
species.richness.nonweighted	Estimates the species richness for a given distance based on given species occurences without using weighting factor.
species.richness.cv		Cross-validates the species richness based on given species occurences.
species.range			Estimates the species range based on given occurences of one species.
extract.species 		Extracts the datasets of one species out of a database filled with species and their occurence locations.
getDimension			Calculates the dimension of the grid which should be used for a species richness estimation.
getShift			Calculates the origin of the grid used for a species richness estimation.
getDistance			Calculates the distance of two points in a grid.
add.Data.to.Grid		Adds the species occurence data to the grid.
add.Edges			Adds an edge between two points to a grid.
edgeNotValid			Checks if an edge would cross a water or mountain surface.
fill.Areas			Fills all bounded areas in a grid.
createLandwatermask		Creates a land-water-mask as a grid based on given dimension and coordinates.
createHeightmask		Creates a height-mask as a grid based on given dimension and coordinates.
generate.subsamples		Creates an array of subsamples of a dataset.
createImage			Creates a levelplot of the result-grid of species range estimation and saves it as a PNG-File.
evaluate 			Evaluates the result grids of species richness estimation and creates a PNG-File with histogramm and statistic information.
exportAsGDAL			Exports the result grid as a GDAL grid map.
createNonInterpolatedGrid	Creates a grid containing the species occurences.
adjustment			Adjusts the weighted species richness for sampling effort.
searchClusters			Searches clusters in the result grid of species richness estimation.
