demoniche_dispersal: Dispersal modelling

In demoniche: demoniche - spatial population dynamics

Description

Inner function. Calculates long and short distance dispersal between populations.

Usage

demoniche_dispersal(seeds_per_population, fraction_LDD, fraction_SDD, dispersal_probabilities, dist_latlong, neigh_index)

Arguments

seeds_per_population
fraction_LDD
fraction_SDD
dispersal_probabilities
dist_latlong
neigh_index

Examples

xs <- expand.grid(seq(1,3, 0.5) ,seq(1,3, 0.5)) # make coordinates
      
dist_latlong <- round(as.matrix(dist(xs)), 1)

neigh_index <- sort(unique(as.numeric(dist_latlong)))[2:3] # find coordinates

seeds_per_population_new <- rep(0,nrow(xs))
seeds_per_population <- sample(c(0,0,10000000), length(seeds_per_population_new), replace = TRUE)

dist_populations <- apply(xs, 1, function(eachPoint) spDistsN1(as.matrix(xs), eachPoint, longlat=TRUE))
  
dispersal_constants <- c(0.7, 0.7, 0.1, 1000)     

dispersal_probabilities <-
 dispersal_constants[1] * dexp((dist_populations * dispersal_constants[3])/dispersal_constants[2])
            
dispersal_probabilities[dist_populations > dispersal_constants[4]] <- 0
  diag(dispersal_probabilities) <- 0  

plot(dispersal_probabilities[,1])
                
        
disp <- 
     demoniche_dispersal(seeds_per_population = seeds_per_population,
     fraction_LDD = 0.05, fraction_SDD = 0.5, dispersal_probabilities = dispersal_probabilities, 
     dist_latlong = dist_latlong, neigh_index = neigh_index)  
                                      
plot(seeds_per_population- disp)

demoniche documentation built on May 2, 2019, 4:45 p.m.