Specify that the SYMPHONY software should be used to solve a conservation planning problem using the lpsymphony package. This function can also be used to customize the behavior of the solver. It requires the lpsymphony package.
add_lpsymphony_solver(x, gap = 0.1, time_limit = 1, first_feasible = 0, verbose = TRUE)
x 


gap 

time_limit 

first_feasible 

verbose 

ConservationProblemclass
object with the solver added
to it.
SYMPHONY is an opensource integer programming solver that is part of the Computational Infrastructure for Operations Research (COINOR) project, an initiative to promote development of opensource tools for operations research (a field that includes linear programming). The lpsymphony package is distributed through Bioconductor. This functionality is provided because the lpsymphony package may be easier to install to install on Windows and Mac OSX systems than the Rsymphony package.
# load data data(sim_pu_raster, sim_features) # create problem p < problem(sim_pu_raster, sim_features) %>% add_min_set_objective() %>% add_relative_targets(0.1) %>% add_binary_decisions()# if the package is installed then add solver and generate solution # note that this solver is skipped on Linux systems due to the fact # that the lpsymphony package randomly crashes on these systems if (require(lpsymphony) & isTRUE(Sys.info()[["sysname"]] != "Linux")) { # specify solver and generate solution s < p %>% add_lpsymphony_solver(time_limit = 5) %>% solve() # plot solutions plot(stack(sim_pu_raster, s), main = c("planning units", "solution")) }#>