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

class StatsampleBivariateTestCase < MiniTest::Unit::TestCase
  should "method sum of squares should be correct" do
    v1=[1,2,3,4,5,6].to_vector(:scale)
    v2=[6,2,4,10,12,8].to_vector(:scale)
    assert_equal(23.0, Statsample::Bivariate.sum_of_squares(v1,v2))
  end
  should "return same covariance with ruby and gls implementation" do
    if Statsample.has_gsl?
      v1=20.times.collect {|a| rand()}.to_scale
      v2=20.times.collect {|a| rand()}.to_scale
      assert_in_delta(Statsample::Bivariate.covariance(v1,v2), Statsample::Bivariate.covariance_slow(v1,v2), 0.001)
    else
      skip "Bivariate::covariance not tested (needs GSL)"
    end

  end

  should "return same correlation with ruby and gls implementation" do
    if Statsample.has_gsl?
      v1=20.times.collect {|a| rand()}.to_scale
      v2=20.times.collect {|a| rand()}.to_scale

      assert_in_delta(GSL::Stats::correlation(v1.gsl, v2.gsl), Statsample::Bivariate.pearson_slow(v1,v2), 1e-10)
    else
      skip "Not tested gsl versus ruby correlation (needs GSL)"
    end
  end
  should "return correct pearson correlation" do
    v1=[6,5,4,7,8,4,3,2].to_vector(:scale)
    v2=[2,3,7,8,6,4,3,2].to_vector(:scale)
    assert_in_delta(0.525,Statsample::Bivariate.pearson(v1,v2), 0.001)
    assert_in_delta(0.525,Statsample::Bivariate.pearson_slow(v1,v2), 0.001)

    v3=[6,2,  1000,1000,5,4,7,8,4,3,2,nil].to_vector(:scale)
    v4=[2,nil,nil,nil,  3,7,8,6,4,3,2,500].to_vector(:scale)
    assert_in_delta(0.525,Statsample::Bivariate.pearson(v3,v4),0.001)
    # Test ruby method
    v3a,v4a=Statsample.only_valid v3, v4
    assert_in_delta(0.525, Statsample::Bivariate.pearson_slow(v3a,v4a),0.001)
  end
  should "return correct values for t_pearson and prop_pearson" do
    v1=[6,5,4,7,8,4,3,2].to_vector(:scale)
    v2=[2,3,7,8,6,4,3,2].to_vector(:scale)
    r=Statsample::Bivariate::Pearson.new(v1,v2)
    assert_in_delta(0.525,r.r, 0.001)
    assert_in_delta(Statsample::Bivariate.t_pearson(v1,v2), r.t, 0.001)
    assert_in_delta(Statsample::Bivariate.prop_pearson(r.t,8,:both), r.probability, 0.001)
    assert(r.summary.size>0)
  end
  should "return correct correlation_matrix" do
    v1=[6,5,4,7,8,4,3,2].to_vector(:scale)
    v2=[2,3,7,8,6,4,3,2].to_vector(:scale)
    v3=[6,2,  1000,1000,5,4,7,8].to_vector(:scale)
    v4=[2,nil,nil,nil,  3,7,8,6].to_vector(:scale)
    ds={'v1'=>v1,'v2'=>v2,'v3'=>v3,'v4'=>v4}.to_dataset
    c=Proc.new {|n1,n2|Statsample::Bivariate.pearson(n1,n2)}
    expected=Matrix[ [c.call(v1,v1),c.call(v1,v2),c.call(v1,v3),c.call(v1,v4)], [c.call(v2,v1),c.call(v2,v2),c.call(v2,v3),c.call(v2,v4)], [c.call(v3,v1),c.call(v3,v2),c.call(v3,v3),c.call(v3,v4)],
      [c.call(v4,v1),c.call(v4,v2),c.call(v4,v3),c.call(v4,v4)]
    ]
    obt=Statsample::Bivariate.correlation_matrix(ds)
    for i in 0...expected.row_size
      for j in 0...expected.column_size
        #puts expected[i,j].inspect
        #puts obt[i,j].inspect
        assert_in_delta(expected[i,j], obt[i,j],0.0001, "#{expected[i,j].class}!=#{obt[i,j].class}  ")
      end
    end
    #assert_equal(expected,obt)
  end
  should "return correct value for prop pearson" do
    assert_in_delta(0.42, Statsample::Bivariate.prop_pearson(Statsample::Bivariate.t_r(0.084,94), 94),0.01)
    assert_in_delta(0.65, Statsample::Bivariate.prop_pearson(Statsample::Bivariate.t_r(0.046,95), 95),0.01)
    r=0.9
    n=100
    t=Statsample::Bivariate.t_r(r,n)
    assert(Statsample::Bivariate.prop_pearson(t,n,:both)<0.05)
    assert(Statsample::Bivariate.prop_pearson(t,n,:right)<0.05)
    assert(Statsample::Bivariate.prop_pearson(t,n,:left)>0.05)

    r=-0.9
    n=100
    t=Statsample::Bivariate.t_r(r,n)
    assert(Statsample::Bivariate.prop_pearson(t,n,:both)<0.05)
    assert(Statsample::Bivariate.prop_pearson(t,n,:right)>0.05)
    assert(Statsample::Bivariate.prop_pearson(t,n,:left)<0.05)
  end

  should "return correct value for Spearman's rho" do
    v1=[86,97,99,100,101,103,106,110,112,113].to_vector(:scale)
    v2=[0,20,28,27,50,29,7,17,6,12].to_vector(:scale)
    assert_in_delta(-0.175758,Statsample::Bivariate.spearman(v1,v2),0.0001)

  end
  should "return correct value for point_biserial correlation" do
    c=[1,3,5,6,7,100,200,300,400,300].to_vector(:scale)
    d=[1,1,1,1,1,0,0,0,0,0].to_vector(:scale)
    assert_raises TypeError do
      Statsample::Bivariate.point_biserial(c,d)
    end
    assert_in_delta(Statsample::Bivariate.point_biserial(d,c), Statsample::Bivariate.pearson(d,c), 0.0001)
  end
  should "return correct value for tau_a and tau_b" do
    v1=[1,2,3,4,5,6,7,8,9,10,11].to_vector(:ordinal)
    v2=[1,3,4,5,7,8,2,9,10,6,11].to_vector(:ordinal)
    assert_in_delta(0.6727,Statsample::Bivariate.tau_a(v1,v2),0.001)
    assert_in_delta(0.6727,Statsample::Bivariate.tau_b((Statsample::Crosstab.new(v1,v2).to_matrix)),0.001)
    v1=[12,14,14,17,19,19,19,19,19,20,21,21,21,21,21,22,23,24,24,24,26,26,27].to_vector(:ordinal)
    v2=[11,4,4,2,0,0,0,0,0,0,4,0,4,0,0,0,0,4,0,0,0,0,0].to_vector(:ordinal)
    assert_in_delta(-0.376201540231705, Statsample::Bivariate.tau_b(Statsample::Crosstab.new(v1,v2).to_matrix),0.001)
  end
  should "return correct value for gamma correlation" do
    m=Matrix[[10,5,2],[10,15,20]]
    assert_in_delta(0.636,Statsample::Bivariate.gamma(m),0.001)
    m2=Matrix[[15,12,6,5],[12,8,10,8],[4,6,9,10]]
    assert_in_delta(0.349,Statsample::Bivariate.gamma(m2),0.001)


  end
end