fr2prob {SESraster} | R Documentation |
Adjust probability of sampling based on frequency of occurrences.
Description
This function is used to adjust the probability of a species to be sampled across the raster, so that the sampled frequency of occurrence of the species is closer to the observed
Usage
fr2prob(x, rprob = NULL)
Arguments
x |
SpatRaster. A presence-absence raster (stack). |
rprob |
SpatRaster. A raster (stack) of probabilities. |
Value
numeric vector
Examples
library(SESraster)
library(terra)
# load random species distributions
r <- load_ext_data()
# applying the function
fr2prob(r)
f <- system.file("ex/elev.tif", package="terra")
r <- rast(f)
set.seed(510)
r10 <- rast(lapply(1:18,
function(i, r, mn, mx){
app(r, function(x, t){
sapply(x, function(x, t){
x<max(t) & x>min(t)
}, t=t)
}, t=sample(seq(mn, mx), 2))
}, r=r, mn=minmax(r)[1]+10, mx=minmax(r)[2]-10))
names(r10) <- paste("sp", 1:nlyr(r10))
fr2prob(r10)
# raw frequencies
unlist(terra::global(r10, function(x)sum(x, na.rm=TRUE)))
[Package SESraster version 0.7.0 Index]