data-raw/simulate-momentu.R

In Freshwater-Fish-Ecology-Laboratory/detrange: Estimate Detection Range from Passive Acoustic Telemetry

library(momentuHMM)
boundary <- forest
boundary[boundary>0] <- NA
boundary <- raster::distance(boundary)
names(boundary) <- "boundary"
proj4string(boundary) <- sp::CRS("+init=epsg:4326")
grad <- ctmcmove::rast.grad(boundary)
grad.x <- grad$rast.grad.x
grad.y <- grad$rast.grad.y

dist <- list(mu="rw_mvnorm2") # bivariate normal random walk
DM <- list(mu=list(mean.x=~mu.x_tm1+crw(mu.x_tm1,lag=1)+grad.x,
                   mean.y=~mu.y_tm1+crw(mu.y_tm1,lag=1)+grad.y,
                   sigma.x=~1,
                   sigma.xy=~1,
                   sigma.y=~1))

Par <- list(mu=c(1,0.75,-750000,1,0.75,-1500,log(100000),0,log(100000)))
names(Par$mu) <- c("mu.x_tm1","crw(mu.x_tm1,lag=1)","grad.x",
                   "mu.y_tm1","crw(mu.y_tm1,lag=1)","grad.y",
                   "sigma.x","sigma.xy","sigma.y")
# simulate and plot
simBound <- simData(nbStates=1, obsPerAnimal = 10000, dist=dist, Par=Par,
                    DM=DM, spatialCovs=list(grad.x = grad.x,
                                            grad.y = grad.y),
                    mvnCoords="mu", initialPosition=c(25000,75000))
plot(simBound,dataNames=c("mu.x","mu.y"),ask=FALSE)
plot(boundary$boundary)
points(simBound$mu.x,simBound$mu.y,type="l")