tests/testthat/test-pFinalSizeAndGen.R

In branchingprocess: Calculate Outbreak Probabilities for a Branching Process Model

test_that("pFinalSizeAndGen() matches brute-force calculation", {
  pfs1 <- pFinalSizeAndGen(g=1, n=1, j=4, R=1.2, k=0.33)
  pfs2 <- pFinalSizeAndGen(g=2, n=1, j=4, R=1.2, k=0.33)
  pfs3 <- pFinalSizeAndGen(g=3, n=1, j=4, R=1.2, k=0.33)

  d <- dnbinom(0:3, mu=1.2, size=0.33)
  dnb1 <- d[4] * d[1]^3
  dnb2 <- d[3] * d[2] * d[1]^2 * 2 +
    d[2] * d[3] * d[1]^2
  dnb3 <- d[2]^3 * d[1]
  
  expect_equal(pfs1, dnb1, tolerance = sqrt(.Machine$double.eps))
  expect_equal(pfs2, dnb2, tolerance = sqrt(.Machine$double.eps))
  expect_equal(pfs3, dnb3, tolerance = sqrt(.Machine$double.eps))
})