maxResNN is a function that can be used to compute a reasonable grid resolution for nearest neighbor based uniform sampling. The core idea behind its working principle is that we want to expect a grid cell to contain points if it overlaps with the environment. This implementation looks at the low density regions using distance to n neighbors as a proxy. The approach assumes that both coordinates have similar range, as the axes are not weighted when computing Neighbors and converting from distances to number of grid cells If multiple points from the same grid cell should be sampled, the number of neighbors included in the computation should be set accordingly
Source:R/maxResNn.R
maxResNn.Rd
maxResNN is a function that can be used to compute a reasonable grid resolution for nearest neighbor based uniform sampling. The core idea behind its working principle is that we want to expect a grid cell to contain points if it overlaps with the environment. This implementation looks at the low density regions using distance to n neighbors as a proxy. The approach assumes that both coordinates have similar range, as the axes are not weighted when computing Neighbors and converting from distances to number of grid cells If multiple points from the same grid cell should be sampled, the number of neighbors included in the computation should be set accordingly
Usage
maxResNn(
env.data.raster,
dimensions = c("PC1", "PC2"),
low.end.of.inclueded.points = 20,
high.end.of.included.points = 4,
n.neighbors = 2,
PCA = FALSE
)
Arguments
- env.data.raster
Raster containing the environmental parameters
- dimensions
vector containing the dimensions that should be used for the grid computation
- low.end.of.inclueded.points
low cutoff
- high.end.of.included.points
high cutoff
- n.neighbors
number of neighbors used for the computation
- PCA
can be set to true if rastPCA was already used to perform a pca to save time recomputing