deepG: deepG

context("preprocess")

test_that("Correct vocabulary extraction", {
  
  expect_equal(getVocabulary("ABC"), c("a", "b", "c"))
  expect_equal(getVocabulary("CBA"), c("a", "b", "c"))
  expect_equal(getVocabulary("AAA"), c("a"))
  expect_equal(getVocabulary("012"), c("0", "1", "2"))
  expect_equal(getVocabulary("()/"), c("(", ")", "/"))
  expect_equal(getVocabulary(" a "), c(" ", "a"))
  expect_equal(getVocabulary("abc"), c("a","b","c"))
  expect_equal(getVocabulary(123),c("1","2","3"))
  expect_equal(getVocabulary(c("A","B","C",1)),c("\n","1","a","b","c"))
  expect_equal(getVocabulary("\n"),c("\n"))
  
  expect_error(getVocabulary(""))
  expect_error(getVocabulary())
  
  expect_is(getVocabulary("abc"),"character")
  
  expect_message(getVocabulary("abc", verbose = T))
  expect_silent(getVocabulary("abc"))
})

test_that("Generating semi-redundant chunks", {
  
  expect_is(preprocessSemiRedundant(char = "abcd", maxlen = 2),"list")
  expect_is(preprocessSemiRedundant(char = "abcd", maxlen = 2)$X,"array")
  expect_is(preprocessSemiRedundant(char = "abcd", maxlen = 2)$Y,"matrix")
  
  expect_equivalent(lengths(preprocessSemiRedundant(char = "abcd", maxlen = 2))[1], 16)
  expect_equivalent(lengths(preprocessSemiRedundant(char = "abcd", maxlen = 2, vocabulary = c("a","b","c","d")))[1], 16)
  expect_equivalent(lengths(preprocessSemiRedundant(char = "abcd", maxlen = 2))[2], 8)
  expect_equivalent(preprocessSemiRedundant(char = "abcd", maxlen = 2)$Y, matrix(c(0,0,1,0,0,0,0,1), byrow = TRUE, nrow = 2))           
  expect_equivalent(length(preprocessSemiRedundant(char="abcd", maxlen = 2)),2)
  
  expect_error(preprocessSemiRedundant(char = "abcd", maxlen = ""))
  expect_error(preprocessSemiRedundant(char = "abcd", maxlen = 0))
  expect_error(preprocessSemiRedundant(char = "abcd", vocabulary = ""))
  expect_error(preprocessSemiRedundant(char = "abcd", vocabulary = 0))
  
  expect_message(preprocessSemiRedundant(char = "abcd", maxlen = 2, verbose = T))
  expect_silent(preprocessSemiRedundant(char = "abcd", maxlen = 2))

  expect_type(preprocessSemiRedundant(char = "abcd", maxlen = 2)$X, "double")
  expect_type(preprocessSemiRedundant(char = "abcd", maxlen = 2)$Y, "double")
})

test_that("Generating semi-redundant chunks from Fasta files", {
  
  file <- file.path("fasta/a.fasta")
  
  expect_is(preprocessFasta(file),"list")
  expect_is(preprocessFasta(file)$X,"array")
  expect_is(preprocessFasta(file)$Y,"matrix")
  
  expect_equivalent(lengths(preprocessFasta(file))[2], 39672)
  expect_equivalent(length(preprocessFasta(file)),2)
  
  expect_error(preprocessFasta())
  expect_error(preprocessFasta(""))
  
  expect_silent(preprocessFasta(file))
  
  expect_type(preprocessFasta(file)$X, "double")
  expect_type(preprocessFasta(file)$Y, "double")
})

# TODO: test shuffling
test_that("Checking the generator for the Fasta files", {
  
  expect_error(sequenceToArray())
  expect_error(sequenceToArray(""))
  
  testpath <- file.path("fasta_2")
  vocabulary = c("a", "c", "g", "t")
  batch.size <- 5
  maxlen <- 3
  gen <- fastaFileGenerator(corpus.dir = testpath, batch.size = batch.size, maxlen = maxlen, showWarnings = FALSE, vocabulary = vocabulary)

  arrays <- gen()

  expect_equivalent(dim(arrays[[1]])[1], batch.size)
  expect_equivalent(dim(arrays[[1]])[2], maxlen)
  expect_equivalent(dim(arrays[[1]])[3], length(vocabulary))
  expect_equivalent(dim(arrays[[2]])[1], batch.size)
  expect_equivalent(dim(arrays[[2]])[2], length(vocabulary))
  expect_equivalent(length(arrays),2)

  # a.fasta file starts with aaccggtt

  expect_equivalent(arrays[[1]][1, 1, ], c(1, 0, 0, 0)) # a
  expect_equivalent(arrays[[1]][1, 2, ], c(1, 0, 0, 0)) # a
  expect_equivalent(arrays[[1]][1, 3, ], c(0, 1, 0, 0)) # c
  expect_equivalent(arrays[[2]][1, ], c(0, 1, 0, 0)) # c

  arrays_2 <- gen()

  expect_equivalent(arrays_2[[1]][2, 1, ], c(1, 0, 0, 0)) # a
  expect_equivalent(arrays_2[[1]][2, 2, ], c(1, 0, 0, 0)) # a
  expect_equivalent(arrays_2[[1]][2, 3, ], c(1, 0, 0, 0)) # a
  expect_equivalent(arrays_2[[2]][2, ], c(0, 0, 0, 1)) # t

  # test transition to second fasta file
  gen <- fastaFileGenerator(corpus.dir = testpath, batch.size = batch.size, maxlen = maxlen, showWarnings = FALSE, vocabulary = vocabulary)
  for (i in 1:5){
  arrays <- gen()
  }
  
  # samples start at beginning of b.fasta
  expect_equivalent(arrays[[1]][1, 1, ], c(1, 0, 0, 0)) # a
  expect_equivalent(arrays[[1]][1, 2, ], c(1, 0, 0, 0)) # a
  expect_equivalent(arrays[[1]][1, 3, ], c(1, 0, 0, 0)) # a
  expect_equivalent(arrays[[2]][1, ], c(1, 0, 0, 0)) # a
  
  expect_equivalent(arrays[[1]][5, 1, ], c(1, 0, 0, 0)) # a
  expect_equivalent(arrays[[1]][5, 2, ], c(1, 0, 0, 0)) # a
  expect_equivalent(arrays[[1]][5, 3, ], c(1, 0, 0, 0)) # a
  expect_equivalent(arrays[[2]][5, ], c(1, 0, 0, 0)) # a
  
  # complete one iteration (100 samples)
  gen <- fastaFileGenerator(corpus.dir = testpath, batch.size = batch.size, maxlen = maxlen, showWarnings = FALSE, vocabulary = vocabulary)
  for (i in 1:9){
    arrays <- gen()
  }
  
  # start from a.fasta again
  expect_equivalent(arrays[[1]][1, 1, ], c(1, 0, 0, 0)) # a
  expect_equivalent(arrays[[1]][1, 2, ], c(1, 0, 0, 0)) # a
  expect_equivalent(arrays[[1]][1, 3, ], c(0, 1, 0, 0)) # c
  expect_equivalent(arrays[[2]][1, ], c(0, 1, 0, 0)) # c
  
  ###################
  # test for different step size
  gen <- fastaFileGenerator(corpus.dir = testpath, batch.size = 4, maxlen = 3, step = 2, showWarnings = FALSE)
  arrays <- gen()
  
  expect_equivalent(arrays[[1]][3, 1, ], c(0, 0, 1, 0)) 
  expect_equivalent(arrays[[1]][3, 2, ], c(0, 0, 1, 0)) 
  expect_equivalent(arrays[[1]][3, 3, ], c(0, 0, 0, 1)) 
  expect_equivalent(arrays[[2]][3, ], c(0, 0, 0, 1)) 
  
  expect_equivalent(arrays[[1]][4, 1, ], c(1, 0, 0, 0)) 
  expect_equivalent(arrays[[1]][4, 2, ], c(1, 0, 0, 0)) 
  expect_equivalent(arrays[[1]][4, 3, ], c(1, 0, 0, 0)) 
  expect_equivalent(arrays[[2]][4, ], c(1, 0, 0, 0)) 

  ####
  # tests with chars outside vocabulary, vocabulary does not contain "A"
  gen <- fastaFileGenerator(corpus.dir = testpath, batch.size = 5, maxlen = 3, step = 2, showWarnings = FALSE, vocabulary = c("c", "g", "t"))
  arrays <- gen()
  
  expect_equivalent(arrays[[1]][1, 1, ], c(0, 0, 0)) # a 
  expect_equivalent(arrays[[1]][1, 2, ], c(0, 0, 0)) # a
  expect_equivalent(arrays[[1]][1, 3, ], c(1, 0, 0)) # c
  expect_equivalent(arrays[[2]][1, ], c(1, 0, 0)) # c
  
  ####
  # test reverse complement
  gen <- fastaFileGenerator(corpus.dir = testpath, batch.size = 6, maxlen = 3, step = 4, showWarnings = FALSE,
                            vocabulary = c("a", "c", "g", "t"), reverseComplements = TRUE)
  arrays <- gen()
  expect_equivalent(arrays[[1]][1, 1, ], c(1, 0, 0, 0))  
  expect_equivalent(arrays[[1]][1, 2, ], c(1, 0, 0, 0)) 
  expect_equivalent(arrays[[1]][1, 3, ], c(0, 1, 0, 0)) 
  expect_equivalent(arrays[[2]][1, ], c(0, 1, 0, 0)) 
  
  expect_equivalent(arrays[[1]][2, 1, ], c(0, 0, 1, 0))  
  expect_equivalent(arrays[[1]][2, 2, ], c(0, 0, 1, 0)) 
  expect_equivalent(arrays[[1]][2, 3, ], c(0, 0, 0, 1)) 
  expect_equivalent(arrays[[2]][2, ], c(0, 0, 0, 1)) 
  
  expect_equivalent(arrays[[1]][3, 1, ], c(1, 0, 0, 0))  
  expect_equivalent(arrays[[1]][3, 2, ], c(1, 0, 0, 0)) 
  expect_equivalent(arrays[[1]][3, 3, ], c(1, 0, 0, 0)) 
  expect_equivalent(arrays[[2]][3, ], c(1, 0, 0, 0)) 
  
  expect_equivalent(arrays[[1]][4, 1, ], c(0, 0, 0, 1))  
  expect_equivalent(arrays[[1]][4, 2, ], c(0, 0, 0, 1)) 
  expect_equivalent(arrays[[1]][4, 3, ], c(0, 0, 0, 1)) 
  expect_equivalent(arrays[[2]][4, ], c(0, 0, 0, 1)) 
  
  expect_equivalent(arrays[[1]][5, 1, ], c(1, 0, 0, 0))  
  expect_equivalent(arrays[[1]][5, 2, ], c(1, 0, 0, 0)) 
  expect_equivalent(arrays[[1]][5, 3, ], c(0, 1, 0, 0)) 
  expect_equivalent(arrays[[2]][5, ], c(0, 1, 0, 0)) 
  
  expect_equivalent(arrays[[1]][6, 1, ], c(0, 0, 1, 0))  
  expect_equivalent(arrays[[1]][6, 2, ], c(0, 0, 1, 0)) 
  expect_equivalent(arrays[[1]][6, 3, ], c(0, 0, 0, 1)) 
  expect_equivalent(arrays[[2]][6, ], c(0, 0, 0, 1)) 
  
  ####
  # test padding
  gen <- fastaFileGenerator(corpus.dir = testpath, batch.size = 1, maxlen = 10, step = 4, showWarnings = FALSE,
                            vocabulary = c("a", "c", "g", "t"))
  arrays <- gen()
  expect_equivalent(arrays[[1]][1, 1, ], c(0, 0, 0, 0))  
  expect_equivalent(arrays[[1]][1, 2, ], c(0, 0, 0, 0)) 
  expect_equivalent(arrays[[1]][1, 3, ], c(0, 0, 0, 0)) 
  expect_equivalent(arrays[[1]][1, 4, ], c(1, 0, 0, 0))  
  expect_equivalent(arrays[[1]][1, 5, ], c(1, 0, 0, 0)) 
  expect_equivalent(arrays[[1]][1, 6, ], c(0, 1, 0, 0)) 
  expect_equivalent(arrays[[1]][1, 7, ], c(0, 1, 0, 0)) 
  expect_equivalent(arrays[[1]][1, 8, ], c(0, 0, 1, 0))  
  expect_equivalent(arrays[[1]][1, 9, ], c(0, 0, 1, 0)) 
  expect_equivalent(arrays[[1]][1, 10, ], c(0, 0, 0, 1)) 
  expect_equivalent(arrays[[2]][1, ], c(0, 0, 0, 1)) 
  
  ####
  
  expect_error(fastaFileGenerator())
  expect_error(fastaFileGenerator(""))
 
  expect_is(fastaFileGenerator(testpath, batch.size = batch.size, maxlen = maxlen, showWarnings = FALSE), "function")
  expect_is(gen(), "list")
  expect_is(gen()[[1]], "array")
  expect_is(gen()[[2]], "matrix")
  
  expect_message(fastaFileGenerator(testpath, batch.size = batch.size, maxlen = maxlen,
                                    showWarnings = FALSE, verbose = T))
  expect_silent(fastaFileGenerator(testpath, batch.size = batch.size, maxlen = maxlen, showWarnings = FALSE))
  
  # no T in vocabulary
  expect_warning(fastaFileGenerator(testpath, batch.size = batch.size, maxlen = maxlen, 
                                    vocabulary = c("a", "c", "g"), showWarnings = TRUE))
  
  
  expect_type(gen()[[1]], "double")
  expect_type(gen()[[2]], "double")
  
  ############# Test label generator (header) #############
  testpath <- file.path("fasta_2")
  
  gen <- fastaLabelGenerator(corpus.dir = testpath, batch.size = 5, maxlen = 3, step = 2, showWarnings = FALSE, vocabulary = c("a", "c", "g", "t"),
                             reverseComplement = FALSE, labelVocabulary = c("w", "x", "y"))
  
  arrays <- gen()
  
  expect_equivalent(arrays[[1]][1, 1, ], c(1, 0, 0, 0)) # A  
  expect_equivalent(arrays[[1]][1, 2, ], c(1, 0, 0, 0)) # A
  expect_equivalent(arrays[[1]][1, 3, ], c(0, 1, 0, 0)) # C
  expect_equivalent(arrays[[2]][1, ], c(1, 0, 0)) # W 
  
  expect_equivalent(arrays[[1]][5, 1, ], c(1, 0, 0, 0)) # A  
  expect_equivalent(arrays[[1]][5, 2, ], c(1, 0, 0, 0)) # A
  expect_equivalent(arrays[[1]][5, 3, ], c(0, 0, 0, 1)) # T
  expect_equivalent(arrays[[2]][5, ], c(0, 1, 0)) # W 
  
  gen <- fastaLabelGenerator(corpus.dir = testpath, batch.size = 8, maxlen = 7, step = 2, showWarnings = FALSE, vocabulary = c("a", "c", "g", "t"),
                             reverseComplement = FALSE, labelVocabulary = c("w", "x", "y"))
  
  arrays <- gen()
  
  # go through a/b.fasta once discard samples with target z
  expect_equivalent(arrays[[1]][8, 1, ], c(1, 0, 0, 0)) # A  
  expect_equivalent(arrays[[1]][8, 2, ], c(1, 0, 0, 0)) # A
  expect_equivalent(arrays[[1]][8, 3, ], c(0, 1, 0, 0)) # C
  expect_equivalent(arrays[[2]][8, ], c(1, 0, 0)) # W 
  
  gen <- fastaLabelGenerator(corpus.dir = testpath, batch.size = 8, maxlen = 7, step = 1, showWarnings = FALSE, vocabulary = c("a", "c", "g", "t"),
                             reverseComplement = TRUE, labelVocabulary = c("w", "x", "y"))
  arrays <- gen()
  # half of batch should be reverse complement
  expect_equivalent(arrays[[1]][1, 7:1,  ], arrays[[1]][5, , c(4,3,2,1)]) 
  expect_equivalent(arrays[[1]][2, 7:1,  ], arrays[[1]][6, , c(4,3,2,1)]) 
  expect_equivalent(arrays[[1]][3, 7:1,  ], arrays[[1]][7, , c(4,3,2,1)])   
  expect_equivalent(arrays[[1]][4, 7:1,  ], arrays[[1]][8, , c(4,3,2,1)]) 
  expect_equivalent(arrays[[2]][1:4, ], arrays[[2]][5:8, ])  
})

############# Test label generator (folder) #############
directories <- c("label_folder/x", "label_folder/y", "label_folder/z")
val <- FALSE
initializeGenerators(directories = directories,
                                 format = "fasta",
                                 batch.size = 6,
                                 maxlen = 2,
                                 vocabulary = c("a", "c", "g", "t"),
                                 step = 2)

gen <- labelByFolderGeneratorWrapper(val = val, path = directories)
arrays <- gen()
expect_equivalent(arrays[[1]][1, 1,  ], c(1, 0, 0, 0))
expect_equivalent(arrays[[1]][1, 2,  ], c(0, 1, 0, 0)) 
expect_equivalent(arrays[[1]][2, 1,  ], c(1, 0, 0, 0))
expect_equivalent(arrays[[1]][2, 2,  ], c(0, 1, 0, 0)) 
expect_equivalent(arrays[[1]][3, 1,  ], c(0, 0, 1, 0))
expect_equivalent(arrays[[1]][3, 2,  ], c(0, 1, 0, 0)) 
expect_equivalent(arrays[[1]][4, 1,  ], c(0, 0, 1, 0))
expect_equivalent(arrays[[1]][4, 2,  ], c(0, 1, 0, 0)) 
expect_equivalent(arrays[[1]][5, 1,  ], c(0, 0, 0, 1))
expect_equivalent(arrays[[1]][5, 2,  ], c(0, 0, 0, 1)) 
expect_equivalent(arrays[[1]][6, 1,  ], c(0, 0, 0, 1))
expect_equivalent(arrays[[1]][6, 2,  ], c(0, 0, 0, 1)) 

expect_equivalent(arrays[[2]][1,  ], c(1, 0, 0)) 
expect_equivalent(arrays[[2]][2,  ], c(1, 0, 0))
expect_equivalent(arrays[[2]][3,  ], c(0, 1, 0)) 
expect_equivalent(arrays[[2]][4,  ], c(0, 1, 0))
expect_equivalent(arrays[[2]][5,  ], c(0, 0, 1)) 
expect_equivalent(arrays[[2]][6,  ], c(0, 0, 1))


# test skipping file 
for (i in 1:2){
  arrays <- gen()
}

expect_equivalent(arrays[[1]][1, 1,  ], c(1, 0, 0, 0))
expect_equivalent(arrays[[1]][1, 2,  ], c(0, 1, 0, 0)) 
expect_equivalent(arrays[[1]][2, 1,  ], c(1, 0, 0, 0))
expect_equivalent(arrays[[1]][2, 2,  ], c(0, 0, 1, 0)) 
expect_equivalent(arrays[[1]][3, 1,  ], c(0, 1, 0, 0))
expect_equivalent(arrays[[1]][3, 2,  ], c(0, 0, 1, 0)) 
expect_equivalent(arrays[[1]][4, 1,  ], c(0, 1, 0, 0))
expect_equivalent(arrays[[1]][4, 2,  ], c(0, 0, 1, 0)) 
expect_equivalent(arrays[[1]][5, 1,  ], c(1, 0, 0, 0))
expect_equivalent(arrays[[1]][5, 2,  ], c(1, 0, 0, 0)) 
expect_equivalent(arrays[[1]][6, 1,  ], c(1, 0, 0, 0))
expect_equivalent(arrays[[1]][6, 2,  ], c(1, 0, 0, 0)) 

expect_equivalent(arrays[[2]][1,  ], c(1, 0, 0)) 
expect_equivalent(arrays[[2]][2,  ], c(1, 0, 0))
expect_equivalent(arrays[[2]][3,  ], c(0, 1, 0)) 
expect_equivalent(arrays[[2]][4,  ], c(0, 1, 0))
expect_equivalent(arrays[[2]][5,  ], c(0, 0, 1)) 
expect_equivalent(arrays[[2]][6,  ], c(0, 0, 1))

# 
arrays <- gen()

expect_equivalent(arrays[[1]][1, 1,  ], c(1, 0, 0, 0))
expect_equivalent(arrays[[1]][1, 2,  ], c(0, 0, 1, 0))
expect_equivalent(arrays[[1]][2, 1,  ], c(1, 0, 0, 0))
expect_equivalent(arrays[[1]][2, 2,  ], c(0, 0, 1, 0)) 
expect_equivalent(arrays[[1]][3, 1,  ], c(0, 0, 1, 0))
expect_equivalent(arrays[[1]][3, 2,  ], c(0, 1, 0, 0)) 
expect_equivalent(arrays[[1]][4, 1,  ], c(0, 0, 1, 0))
expect_equivalent(arrays[[1]][4, 2,  ], c(0, 1, 0, 0)) 
expect_equivalent(arrays[[1]][5, 1,  ], c(1, 0, 0, 0))
expect_equivalent(arrays[[1]][5, 2,  ], c(1, 0, 0, 0)) 
expect_equivalent(arrays[[1]][6, 1,  ], c(1, 0, 0, 0))
expect_equivalent(arrays[[1]][6, 2,  ], c(1, 0, 0, 0)) 

expect_equivalent(arrays[[2]][1,  ], c(1, 0, 0)) 
expect_equivalent(arrays[[2]][2,  ], c(1, 0, 0))
expect_equivalent(arrays[[2]][3,  ], c(0, 1, 0)) 
expect_equivalent(arrays[[2]][4,  ], c(0, 1, 0))
expect_equivalent(arrays[[2]][5,  ], c(0, 0, 1)) 
expect_equivalent(arrays[[2]][6,  ], c(0, 0, 1))

# reverse complement

initializeGenerators(directories = directories,
                     format = "fasta",
                     batch.size = 6,
                     maxlen = 2,
                     vocabulary = c("a", "c", "g", "t"),
                     reverseComplements = TRUE, 
                     step = 100)

gen <- labelByFolderGeneratorWrapper(val = val, path = directories)
arrays <- gen()
expect_equivalent(arrays[[1]][1, 1,  ], c(1, 0, 0, 0))
expect_equivalent(arrays[[1]][1, 2,  ], c(0, 1, 0, 0)) 
expect_equivalent(arrays[[1]][2, 1,  ], c(0, 0, 1, 0))
expect_equivalent(arrays[[1]][2, 2,  ], c(0, 0, 0, 1)) 
expect_equivalent(arrays[[1]][3, 1,  ], c(0, 0, 1, 0))
expect_equivalent(arrays[[1]][3, 2,  ], c(0, 1, 0, 0)) 
expect_equivalent(arrays[[1]][4, 1,  ], c(0, 0, 1, 0))
expect_equivalent(arrays[[1]][4, 2,  ], c(0, 1, 0, 0)) 
expect_equivalent(arrays[[1]][5, 1,  ], c(0, 0, 0, 1))
expect_equivalent(arrays[[1]][5, 2,  ], c(0, 0, 0, 1)) 
expect_equivalent(arrays[[1]][6, 1,  ], c(1, 0, 0, 0))
expect_equivalent(arrays[[1]][6, 2,  ], c(1, 0, 0, 0)) 

expect_equivalent(arrays[[2]][1,  ], c(1, 0, 0)) 
expect_equivalent(arrays[[2]][2,  ], c(1, 0, 0))
expect_equivalent(arrays[[2]][3,  ], c(0, 1, 0)) 
expect_equivalent(arrays[[2]][4,  ], c(0, 1, 0))
expect_equivalent(arrays[[2]][5,  ], c(0, 0, 1)) 
expect_equivalent(arrays[[2]][6,  ], c(0, 0, 1))

# 
arrays <- gen()

expect_equivalent(arrays[[1]][1, 1,  ], c(1, 0, 0, 0))
expect_equivalent(arrays[[1]][1, 2,  ], c(0, 0, 1, 0)) 
expect_equivalent(arrays[[1]][2, 1,  ], c(0, 1, 0, 0))
expect_equivalent(arrays[[1]][2, 2,  ], c(0, 0, 0, 1)) 
expect_equivalent(arrays[[1]][3, 1,  ], c(0, 1, 0, 0))
expect_equivalent(arrays[[1]][3, 2,  ], c(0, 0, 1, 0)) 
expect_equivalent(arrays[[1]][4, 1,  ], c(0, 1, 0, 0))
expect_equivalent(arrays[[1]][4, 2,  ], c(0, 0, 1, 0)) 
expect_equivalent(arrays[[1]][5, 1,  ], c(0, 0, 0, 1))
expect_equivalent(arrays[[1]][5, 2,  ], c(0, 0, 0, 1)) 
expect_equivalent(arrays[[1]][6, 1,  ], c(1, 0, 0, 0))
expect_equivalent(arrays[[1]][6, 2,  ], c(1, 0, 0, 0)) 

expect_equivalent(arrays[[2]][1,  ], c(1, 0, 0)) 
expect_equivalent(arrays[[2]][2,  ], c(1, 0, 0))
expect_equivalent(arrays[[2]][3,  ], c(0, 1, 0)) 
expect_equivalent(arrays[[2]][4,  ], c(0, 1, 0))
expect_equivalent(arrays[[2]][5,  ], c(0, 0, 1)) 
expect_equivalent(arrays[[2]][6,  ], c(0, 0, 1))

# 
arrays <- gen()
expect_equivalent(arrays[[1]][1, 1,  ], c(1, 0, 0, 0))
expect_equivalent(arrays[[1]][1, 2,  ], c(0, 1, 0, 0)) 
expect_equivalent(arrays[[1]][2, 1,  ], c(0, 0, 1, 0))
expect_equivalent(arrays[[1]][2, 2,  ], c(0, 0, 0, 1)) 
expect_equivalent(arrays[[1]][3, 1,  ], c(0, 0, 1, 0))
expect_equivalent(arrays[[1]][3, 2,  ], c(0, 1, 0, 0)) 
expect_equivalent(arrays[[1]][4, 1,  ], c(0, 0, 1, 0))
expect_equivalent(arrays[[1]][4, 2,  ], c(0, 1, 0, 0)) 
expect_equivalent(arrays[[1]][5, 1,  ], c(1, 0, 0, 0))
expect_equivalent(arrays[[1]][5, 2,  ], c(1, 0, 0, 0)) 
expect_equivalent(arrays[[1]][6, 1,  ], c(0, 0, 0, 1))
expect_equivalent(arrays[[1]][6, 2,  ], c(0, 0, 0, 1)) 

expect_equivalent(arrays[[2]][1,  ], c(1, 0, 0)) 
expect_equivalent(arrays[[2]][2,  ], c(1, 0, 0))
expect_equivalent(arrays[[2]][3,  ], c(0, 1, 0)) 
expect_equivalent(arrays[[2]][4,  ], c(0, 1, 0))
expect_equivalent(arrays[[2]][5,  ], c(0, 0, 1)) 
expect_equivalent(arrays[[2]][6,  ], c(0, 0, 1))