tests/testthat/test-rhs.R

In RxODE: Facilities for Simulating from ODE-Based Models

rxodeTest(
  {
    library(RxODE)
    library(dplyr)
    library(digest)

    context("rxSolve right handed differental equations")

    rxSetIni0(FALSE)

    orhs <- RxODE("
x(0)    = 1
a       = 1.0E4
d/dt(x) = a*y*z - 0.04*x
d/dt(z) = 3.0e7*y^2
d/dt(y) = -1.0*(d/dt(x)+d/dt(z))
")


    et <- eventTable()
    et$add.sampling(c(4 * 10^seq(-1, 10)))

    ## print(o1);
    test_that("rxSolve produces the correct results for rhs", {
      o1 <- expect_warning(rxSolve(orhs, et))

      ## expect_warning(rxSolve(orhs,et),"The initial conditions are at t = 0.4 instead of t = 0.")
      expect_equal(round(as.data.frame(o1), 4),
        structure(list(time = c(
          0.4, 4, 40, 400, 4000, 40000, 4e+05,
          4e+06, 4e+07, 4e+08, 4e+09, 4e+10
        ), x = c(
          1, 0.9117, 0.7168,
          0.4506, 0.1832, 0.039, 0.0049, -832.9988, -18106.8843, -190902.2423,
          -1918897.229, -19198891.1895
        ), z = c(
          0, 0.0882, 0.2831, 0.5494,
          0.8168, 0.961, 0.9951, 833.9988, 18107.8843, 190903.2423, 1918898.229,
          19198892.1895
        ), y = c(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0)), row.names = c(
          NA,
          -12L
        ), class = "data.frame"),
        tolerance = 1e-4
      )

      o1$add.sampling(0)

      expect_equal(round(as.data.frame(o1), 4),
        structure(list(time = c(
          0, 0.4, 4, 40, 400, 4000, 40000, 4e+05,
          4e+06, 4e+07, 4e+08, 4e+09, 4e+10
        ), x = c(
          1, 0.9852, 0.9055,
          0.7158, 0.4505, 0.1832, 0.039, 0.0049, -832.9941, -18106.8732,
          -190902.279, -1918898.6518, -19198893.9661
        ), z = c(
          0, 0.0148,
          0.0945, 0.2842, 0.5495, 0.8168, 0.961, 0.9951, 833.9941, 18107.8732,
          190903.279, 1918899.6518, 19198894.9661
        ), y = c(
          0, 0, 0, 0, 0,
          0, 0, 0, 0, 0, 0, 0, 0
        )), row.names = c(NA, 13L), class = "data.frame"),
        tolerance = 1e-4
      )
    })

    rxSetIni0(TRUE)
  },
  silent = TRUE,
  test = "lvl2"
)