
Set an objective to maximize effective mesh size
Source:R/set_max_mesh_objective.R
set_max_mesh_objective.Rd
Specify that a restoration problem (restopt_problem()
) should
maximize effective mesh size.
Arguments
- problem
restopt_problem()
Restoration problem object.
Value
An updated restoration problem (restopt_problem()
) object.
Details
The effective mesh size (MESH) is a measure of landscape fragmentation based on the probability that two randomly chosen points are located in the same patch (Jaeger, 2000). Maximizing it in the context of restoration favours fewer and larger patches.
References
Jaeger, J. A. G. (2000). Landscape division, splitting index, and effective mesh size: New measures of landscape fragmentation. Landscape Ecology, 15(2), 115‑130. https://doi.org/10.1023/A:1008129329289
See also
Other objectives:
set_max_iic_objective()
,
set_max_nb_pus_objective()
,
set_max_restore_objective()
,
set_min_nb_patches_objective()
,
set_min_nb_pus_objective()
,
set_min_restore_objective()
,
set_no_objective()
Examples
if (FALSE) { # \dontrun{
# load data
habitat_data <- rast(
system.file("extdata", "habitat_hi_res.tif", package = "restoptr")
)
locked_out_data <- rast(
system.file("extdata", "locked_out.tif", package = "restoptr")
)
# plot data
plot(rast(list(habitat_data, locked_out_data)), nc = 2)
# create problem with locked out constraints
p <- restopt_problem(
existing_habitat = habitat_data,
aggregation_factor = 16,
habitat_threshold = 0.7
) %>%
set_max_mesh_objective() %>%
add_restorable_constraint(
min_restore = 5,
max_restore = 5,
) %>%
add_locked_out_constraint(data = locked_out_data) %>%
add_settings(time_limit = 1)
# print problem
print(p)
# solve problem
s <- solve(p)
# plot solution
plot(s)
} # }