# NOT RUN {
##### Lotka-Volterra equations #####
LVmod <- function(Time, State, Pars) {
with(as.list(c(State, Pars)), {
Ingestion <- rIng * Prey * Predator
GrowthPrey <- rGrow * Prey * (1 - Prey/K)
MortPredator <- rMort * Predator
dPrey <- GrowthPrey - Ingestion
dPredator <- Ingestion * assEff - MortPredator
return(list(c(dPrey, dPredator)))
})
}
LVpars <- c("rIng", "rGrow", "rMort", "assEff", "K")
LVbinf <- c(0.05, 0.05, 0.05, 0.05, 1)
LVbsup <- c(1.00, 3.00, 0.95, 0.95, 20)
LVinit <- c(Prey = 1, Predator = 2)
LVtimes <- c(0.01, seq(1, 50, by = 1))
set.seed(59281)
# Warning: The following code might take very long!
# }
# NOT RUN {
LVres_sobol <- ODEsobol(mod = LVmod,
pars = LVpars,
state_init = LVinit,
times = LVtimes,
n = 500,
rfuncs = "runif",
rargs = paste0("min = ", LVbinf,
", max = ", LVbsup),
sobol_method = "Martinez",
ode_method = "lsoda",
parallel_eval = TRUE,
parallel_eval_ncores = 2)
my_cols <- c("firebrick", "orange2", "dodgerblue",
"forestgreen", "black")
plot(LVres_sobol, colors_pars = my_cols)
plot(LVres_sobol, pars_plot = c("rGrow", "rMort"), state_plot = "Predator",
colors_pars = my_cols[2:3])
# }
# NOT RUN {
##### A network of 4 mechanical oscillators connected in a circle #####
M_mat <- rep(2, 4)
K_mat <- diag(rep(2 * (2*pi*0.17)^2, 4))
K_mat[1, 2] <- K_mat[2, 3] <-
K_mat[3, 4] <- K_mat[1, 4] <- 2 * (2*pi*0.17)^2 / 10
D_mat <- diag(rep(0.05, 4))
library("ODEnetwork")
lfonet <- ODEnetwork(masses = M_mat, dampers = D_mat, springs = K_mat)
LFOpars <- c("k.1", "k.2", "k.3", "k.4",
"d.1", "d.2", "d.3", "d.4")
LFObinf <- c(rep(0.2, 4), rep(0.01, 4))
LFObsup <- c(rep(20, 4), rep(0.1, 4))
lfonet <- setState(lfonet, state1 = rep(2, 4), state2 = rep(0, 4))
LFOtimes <- seq(25, 150, by = 2.5)
set.seed(1739)
# Warning: The following code might take very long!
# }
# NOT RUN {
suppressWarnings(
LFOres_sobol <- ODEsobol(mod = lfonet,
pars = LFOpars,
times = LFOtimes,
n = 500,
rfuncs = "runif",
rargs = paste0("min = ", LFObinf,
", max = ", LFObsup),
sobol_method = "Martinez",
parallel_eval = TRUE,
parallel_eval_ncores = 2)
)
plot(LFOres_sobol, pars_plot = paste0("k.", 1:4), state_plot = "x.2",
colors_pars = my_cols)
# }
# NOT RUN {
# }
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