Converts a population density raster into a probability mass function (PMF)
where all cell values sum to 1. Useful for spatial sampling where probability
of selection should be proportional to population density.
Usage
transform_pmf(x, return_total = FALSE, snap = FALSE)
Arguments
- x
SpatRaster of density values (e.g., population density)
- return_total
logical; if TRUE, returns a list containing both PMF raster
and total population. If FALSE (default), returns only PMF raster
- snap
Logical; if TRUE skip validation and verification
Value
If return_total = FALSE, returns SpatRaster containing probability values
that sum to 1. If return_total = TRUE, returns a list with components:
Examples
# Basic usage
pop_density <- terra::rast(matrix(1:100, 10, 10))
pmf <- transform_pmf(pop_density)
# Get PMF and total population
result <- transform_pmf(pop_density, return_total = TRUE)
pmf <- result$pmf
total_pop <- result$total