tests/testthat/test-forestfire.R

In igraph: Network Analysis and Visualization

test_that("sample_forestfire works", {
  set.seed(42)

  pars <- list(
    sparse = c(0.35, 0.2 / 0.35),
    densifying = c(0.37, 0.32 / 0.37),
    dense = c(0.38, 0.38 / 0.37)
  )

  N <- 5000
  G <- lapply(pars, function(x) sample_forestfire(N, fw.prob = x[1], bw.factor = x[2]))

  xv <- log(2:N)

  co <- sapply(G, function(x) {
    yv <- log(cumsum(degree(x, mode = "out"))[-1])
    coef(lm(yv ~ xv))[2]
  })

  expect_that(co, equals(structure(
    c(
      1.06045500245466,
      1.22800967143684,
      1.96234121488344
    ),
    .Names = c(
      "sparse.xv",
      "densifying.xv", "dense.xv"
    )
  )))
})