tests/testthat/test-mcmc-map.R

In mcmcr: Manipulate MCMC Samples

test_that("mcmc_map", {
  expect_identical(mcmc_map(mcmcr_example[[1]], identity), mcmcr_example[[1]])
  expect_identical(
    mcmc_map(mcmcr_example[[1]], function(x) x * 10),
    mcmcr_example[[1]] * 10
  )
  expect_identical(
    mcmc_map(as.mcmc.list(mcmcr_example[[1]]), function(x) x * 10),
    as.mcmc.list(mcmcr_example[[1]] * 10)
  )
  expect_error(mcmc_map(mcmcr_example[[1]], function(x) c(x, x)))
  expect_identical(
    sum(mcmc_map(mcmcr_example[[1]], function(x) (x * 2))),
    sum(mcmcr_example[[1]]) * 2
  )
  expect_s3_class(mcmc_map(mcmcr_example, function(x) x * 5), "mcmcr")
  expect_identical(
    mcmc_map(mcmcr_example, function(x) x * 5)[[2]],
    mcmcr_example[[2]] * 5
  )
})

test_that("mcmc_map with vector", {
  expect_identical(
    mcmc_map(mcmcr_example[[1]], .f = function(x) x / 1, .by = TRUE),
    mcmcr_example[[1]]
  )
  expect_identical(
    mcmc_map(mcmcr_example[[1]], .f = function(x) x / 1, .by = FALSE),
    mcmcr_example[[1]]
  )
  expect_identical(
    estimates(mcmc_map(
      mcmcr_example[[1]],
      .f = function(x) x / sum(x),
      .by = TRUE
    )),
    c(1, 1)
  )
  expect_equal(
    estimates(mcmc_map(
      mcmcr_example[[1]],
      .f = function(x) x / sum(x),
      .by = FALSE
    )),
    c(0.4407305, 0.5592695),
    tolerance = 1e-07
  )
})

test_that("mcmc_map with arrays identical", {
  x <- array(1:prod(2:7), dim = 2:7)
  class(x) <- "mcmcarray"
  expect_identical(mcmc_map(x, .f = identity), x)
  expect_identical(mcmc_map(x, .f = identity, .by = TRUE), x)
  expect_identical(mcmc_map(x, .f = identity, .by = FALSE), x)
  expect_identical(mcmc_map(x, .f = identity, .by = 1L), x)
  expect_identical(mcmc_map(x, .f = identity, .by = 2L), x)
  expect_identical(mcmc_map(x, .f = identity, .by = c(2L, 4L)), x)
})

test_that("mcmc_map with arrays rescale", {
  x <- array(1:prod(2:7), dim = 2:7)
  class(x) <- "mcmcarray"
  expect_identical(
    estimates(mcmc_map(x, .f = function(x) x / sum(x))),
    array(1, dim = 4:7)
  )
  expect_identical(
    sum(estimates(mcmc_map(x, .f = function(x) x / sum(x)))),
    840
  )
  expect_equal(
    sum(estimates(mcmc_map(x, .f = function(x) x / sum(x), .by = FALSE))),
    1
  )
  expect_identical(
    sum(estimates(mcmc_map(x, .f = function(x) x / sum(x), .by = c(2L, 4L)))),
    35
  )
})