tests/testthat/test_small.R

In umap: Uniform Manifold Approximation and Projection

## tests for small datasets

## ############################################################################
## General expected behavior

test_that("empty dataset gives empty layout", {
  # empty dataset
  i0 <- iris[c(),]
  expect_warning(umap(i0), "small")
  # result should still be well-formed
  result <- suppressWarnings(umap(i0))
  expect_equal(sort(names(result)), c("config", "layout"))
})

test_that("single-item dataset", {
  # empty dataset
  i1 <- iris[1,1:3]
  rownames(i1) <- "A"
  expect_warning(umap(i1), "small")
  # result should still be well-formed
  result <- suppressWarnings(umap(i1))
  expect_equal(sort(names(result)), c("config", "layout"))
  expected <- matrix(0, ncol=2, nrow=1)
  rownames(expected) <- "A"
  expect_equal(result$layout, expected)
})

test_that("two-item dataset", {
  # empty dataset
  i2 <- iris[1:2,1:3]
  rownames(i2) <- c("A", "B")
  expect_warning(umap(i2), "small")
  # result should still be well-formed
  result <- suppressWarnings(umap(i2))
  expect_equal(sort(names(result)), c("config", "layout"))
  expect_equal(dim(result$layout), c(2,2))
  expect_gt(sum(abs(result$layout[1,]-result$layout[2,])), 0)
})