R: Base function to compute AOO with grid uncertainty...

gridUncertaintyBase {redlistr}

R Documentation

Base function to compute AOO with grid uncertainty systematically

Description

gridUncertaintyBase helps determine the minimum number of area of occupancy (AOO) grid cells occupied by a species or ecosystem. It varies the location of the AOO grid by shifting in systematically in both x- and y- axes, adding a small amount of random movement (five percent of the grid.size) at each point. It then returns summary statistics for the range of AOOs calculated, and the RasterLayer(s) containing the grids with the minimum AOO. It is the base function which is used by gridUncertainty, gridUncertaintySimulation, and gridUncertaintyRestricted

Usage

gridUncertaintyBase(
  input.data,
  grid.size,
  splits,
  min.percent.rule = FALSE,
  percent = 1,
  restriction = FALSE,
  min.grids.shift
)

Arguments

`input.data`	Spatial object of an ecosystem or species distribution. Please use a CRS with units measured in metres.
`grid.size`	A number specifying the width of the desired grid square (in same units as your coordinate reference system)
`splits`	Specifies the number of ways to split the grid in ONE axis.
`min.percent.rule`	Logical. If `TRUE`, a minimum area threshold must be passed before a grid is counted as an AOO grid.
`percent`	Numeric. The minimum percent to be applied as a threshold for the `min.percent.rule`.
`restriction`	Logical. If `TRUE`, allows user to specify areas to focus where grid search is done. Used in gridUncertaintyRestricted.
`min.grids.shift`	Dataframe object with two columns (x.shift and y.shift) specifying the coordinates to restrict the AOO grid placement.

Value

List containing the following:

Vector of length split*split of calculated AOO for each shifted grid
Data frame of summary statistics for the results create the AOO grid(s) which return the smallest AOO
Data frame of the shift(s) required to create the AOO grid(s) with the smallest AOO

Author(s)