demo-RxODE.R

## Author: Ruben Faelens, 2021
## Goal: demo for RxODE use
## See https://nlmixrdevelopment.github.io/RxODE/articles/RxODE-sim-var.html for more examples

library(tidyverse)
library(RxODE)
modelCode <- "

KA = THETA1;
V = THETA2 * exp(ETA1) * (BW/70);
CL = THETA3 * exp(ETA2) * (BW/70)**0.75;
Ke = CL/V;

d/dt(A0) = -KA*A0;
d/dt(A1) = KA*A0 - Ke*A1;

CONC = A1 / V
"

m1 <- RxODE::RxODE(modelCode)



## Simulate from a dataset
N <- 100

theta <- c(THETA1=0.05,
             THETA2=2,
             THETA3=0.1)
omega <- lotri(ETA1 + ETA2 ~ c(0.4^2, 0, 0.3^2))

events <- eventTable() %>%
  add.dosing(dose=10, nbr.doses=10, dosing.interval=48) %>%
  add.sampling(time=seq(0, 100, by=0.1))

db <- tibble(
  ID=seq_len(N),
  BW=rnorm(N, 70, 0.10*70)
)
db <- expand_grid(db, events$get.EventTable())

sim  <- rxSolve(m1, theta, db, omega=omega)

ggplot(sim, aes(x=time, y=CONC)) +
#  geom_line(aes(group=id)) +
  stat_summary(fun=mean, color='red') +
  stat_summary(fun="mean_cl_boot", geom="ribbon")