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Simulate spatial point process

simul_spat.Rd

Generates a spatial point process from a reference map, using Inhomogeneous Poisson Point Process with spatstat IPP. The intensity of the process is proportional to this reference map, and the final number of individuals in the population is provided by N. Several runs can be simulated at the same time. If working in a real environment, reference map must be projected.

Usage

simul_spat(
  ref_map,
  N,
  seed = NULL,
  n_sim = 1,
  return_wgs_coordinates = TRUE,
  drop_geometry = FALSE,
  mean_group_size = NULL
)

Arguments

ref_map

Reference map, must be projected

N

Number of individuals in the final population

seed

Numeric

n_sim

Number of simulation to run

return_wgs_coordinates

Boolean. Should the function returns points in WGS coordinates? Recommended when working on real environment

drop_geometry

Boolean. Should the geometry be dropped in returned object? Defaults to FALSE, if TRUE the function will return a data.frame and not a sf object.

mean_group_size

The mean group size to generate the mark. Set to NULL if no mark is wanted.

Value

Returns an sf object

See also

generate_resource_layer generate_env_layer

Examples

grid <- create_grid()
cdt <- generate_env_layer(grid = grid)
#> [using unconditional Gaussian simulation]
rsce <- generate_resource_layer(env_layers = cdt$rasters,
                            beta = c(2, -1.5))

# issue a warning: we are in a virtual env and ref_map has no crs
out <- simul_spat(ref_map = rsce$rasters, n_sim = 2, 
                  return_wgs_coordinates = FALSE, N = 1000, mean_group_size = 10)
#> Warning: ref_map has no crs, is that voluntary? The output will have no crs.

# plot the simulated distribution
ggplot2::ggplot(out) +
  ggplot2::geom_tile(data = rsce$dataframe, ggplot2::aes(x = x, y = y, fill = suitability)) + 
  ggplot2::geom_sf() + ggplot2::facet_wrap("name") +
  viridis::scale_fill_viridis(option = "H")


# check the generated group size
ggplot2::ggplot(out) +
   ggplot2::geom_sf(ggplot2::aes(size = size)) + ggplot2::facet_wrap("name")