tests/testthat/test-rotate.R

In dendextend: Extending 'dendrogram' Functionality in R

# library(testthat)

context("Rotate a tree around its hinges")


test_that("Rotate a dendrogram", {
  hc <- hclust(dist(USArrests[1:3, ]), "ave")
  dend <- as.dendrogram(hc)

  #    labels(dend)
  #    rev(labels(dend))

  expect_equal(rev(labels(dend)), labels(rotate(dend, 3:1)))
  expect_equal(rev(labels(dend)), labels(rotate(dend, rev(labels(dend)))))
})


test_that("Rotate a dendrogram (but not exactly to what we asked for)", {
  hc <- hclust(dist(USArrests[1:3, ]), "ave")
  dend <- as.dendrogram(hc)

  new_order <- c(3, 1, 2) # an impossible order, will fail
  expect_false(all(labels(dend)[new_order] == labels(rotate(dend, new_order))))
  expect_false(all(labels(dend)[new_order] == labels(rotate(dend, labels(dend)[new_order]))))
  #    plot(rotate(dend, new_order))
  #    plot(dend)
})



test_that("Rotate a dendrogram - works with either numeric or character", {
  hc <- hclust(dist(USArrests[1:3, ]), "ave")
  dend <- as.dendrogram(hc)

  new_order <- c(2, 3, 1) # a possible order

  expect_equivalent(rotate(dend, new_order), rotate(dend, labels(dend)[new_order]))
  #    plot(rotate(dend, new_order))
  #    plot(rotate(dend, labels(dend)[new_order]) )
  #    match(labels(dend)[new_order], labels(dend)) # NEW-OLD
  #    new_order
  expect_equivalent(
    labels(rotate(dend, new_order)),
    labels(rotate(dend, labels(dend)[new_order]))
  )
})







test_that("Rotate hclust", {
  hc <- hclust(dist(USArrests[1:3, ]), "ave")

  #    labels(hc)
  #    rev(labels(hc))
  #    plot(hc)
  #    plot(rotate(hc, 3:1))

  expect_equal(rev(labels(hc)), labels(rotate(hc, 3:1)))
  expect_equal(rev(labels(hc)), labels(rotate(hc, rev(labels(hc)))))
})


test_that("Rotate a hclust (but not exactly to what we asked for)", {
  hc <- hclust(dist(USArrests[1:3, ]), "ave")

  new_order <- c(3, 1, 2) # an impossible order, will fail
  expect_false(all(labels(hc)[new_order] == labels(rotate(hc, new_order))))
  expect_false(all(labels(hc)[new_order] == labels(rotate(hc, labels(hc)[new_order]))))
  #    plot(rotate(hc, new_order))
  #    plot(hc)
})