tests/testthat/test-issue-161.R

In nlmixr: Nonlinear Mixed Effects Models in Population PK/PD

nlmixrTest(
  {
    context("Back-transform vs scaling checks (#161)")
    test_that("Log-scaled vs Back-transformed parameters", {
      run7.mod <- function() {
        ini({
          tcl <- log(0.008) # typical value of clearance
          tv <- log(0.6) # typical value of volume
          all.cl <- 1 # allometric exponent on CL
          eta.cl ~ 1
          # interindividual variability on clearance and volume
          add.err <- 0.1 # residual variability
        })
        model({
          cl <- exp(tcl + all.cl * log_allo_wt + eta.cl) # individual value of clearance
          v <- exp(tv) # individual value of volume
          ke <- cl / v # elimination rate constant
          d / dt(A1) <- -ke * A1 # model differential equation
          cp <- A1 / v # concentration in plasma
          cp ~ add(add.err) # define error model
        })
      }

      f <- nlmixr(run7.mod)

      expect_equal(list(1:3, 1:2), f$logThetasList)
    })
  },
  test = "cran"
)