test_that("multiplication works", {
  expect_equal(2 * 2, 4)
})

test_that("sim_qmatrix returns correct dimensions", {
  Q <- sim_qmatrix(J = 5, K = 3)
  expect_true(is.matrix(Q))
  expect_equal(dim(Q), c(5, 3))
})

test_that("structure = 'identity' works", {
  Q <- sim_qmatrix(J = 5, K = 3, structure = "identity")
  expect_equal(ncol(Q), 3)
  expect_true(all(Q %in% c(0, 1)))
})