require(File.expand_path(File.dirname(__FILE__) + '/helpers_tests.rb'))

class StatsampleTestTestCase < Minitest::Test
  def test_chi_square_matrix_with_expected
    real = Matrix[[95, 95], [45, 155]]
    expected = Matrix[[68, 122], [72, 128]]
    assert_nothing_raised do
      Statsample::Test.chi_square(real, expected)
    end
    chi = Statsample::Test.chi_square(real, expected).chi_square
    assert_in_delta(32.53, chi, 0.1)
  end

  def test_chi_square_matrix_only_observed
    observed = Matrix[[20, 30, 40], [30, 40, 50], [60, 70, 80], [10, 20, 40]]
    assert_nothing_raised do
      Statsample::Test.chi_square(observed)
    end
    chi = Statsample::Test.chi_square(observed)
    assert_in_delta(9.5602, chi.chi_square, 0.0001)
    assert_in_delta(0.1444, chi.probability, 0.0001)

    assert_equal(6, chi.df)
  end

  def test_u_mannwhitney
    a = [1, 2, 3, 4, 5, 6].to_numeric
    b = [0, 5, 7, 9, 10, 11].to_numeric
    assert_equal(7.5, Statsample::Test.u_mannwhitney(a, b).u)
    assert_equal(7.5, Statsample::Test.u_mannwhitney(b, a).u)
    a = [1, 7, 8, 9, 10, 11].to_numeric
    b = [2, 3, 4, 5, 6, 12].to_numeric
    assert_equal(11, Statsample::Test.u_mannwhitney(a, b).u)
  end

  def test_levene
    a = [1, 2, 3, 4, 5, 6, 7, 8, 100, 10].to_numeric
    b = [30, 40, 50, 60, 70, 80, 90, 100, 110, 120].to_numeric
    levene = Statsample::Test::Levene.new([a, b])
    assert_levene(levene)
  end

  def test_levene_dataset
    a = [1, 2, 3, 4, 5, 6, 7, 8, 100, 10].to_numeric
    b = [30, 40, 50, 60, 70, 80, 90, 100, 110, 120].to_numeric
    ds = { 'a' => a, 'b' => b }.to_dataset
    levene = Statsample::Test::Levene.new(ds)
    assert_levene(levene)
  end

  def assert_levene(levene)
    assert_in_delta(0.778, levene.f, 0.001)
    assert_in_delta(0.389, levene.probability, 0.001)
  end
end