def test_lagged_mi():
    """Test estimation of lagged MI."""
    n = 10000
    cov = 0.4
    source = [rn.normalvariate(0, 1) for r in range(n)]
    target = [0] + [sum(pair) for pair in zip(
                        [cov * y for y in source[0:n - 1]],
                        [(1 - cov) * y for y in
                            [rn.normalvariate(0, 1) for r in range(n - 1)]])]
    source = np.array(source)
    target = np.array(target)
    settings = {
        'discretise_method': 'equal',
        'n_discrete_bins': 4,
        'history': 1,
        'history_target': 1,
        'lag_mi': 1,
        'source_target_delay': 1}

    est_te_k = JidtKraskovTE(settings)
    te_k = est_te_k.estimate(source, target)
    est_te_d = JidtDiscreteTE(settings)
    te_d = est_te_d.estimate(source, target)
    est_d = JidtDiscreteMI(settings)
    mi_d = est_d.estimate(source, target)
    est_k = JidtKraskovMI(settings)
    mi_k = est_k.estimate(source, target)
    est_g = JidtGaussianMI(settings)
    mi_g = est_g.estimate(source, target)
    _compare_result(mi_d, te_d, 'JidtDiscreteMI', 'JidtDiscreteTE',
                    'lagged MI', tol=0.05)
    _compare_result(mi_k, te_k, 'JidtKraskovMI', 'JidtKraskovTE',
                    'lagged MI', tol=0.05)
    _compare_result(mi_g, te_k, 'JidtGaussianMI', 'JidtKraskovTE',
                    'lagged MI', tol=0.05)
def test_one_two_dim_input_kraskov():
    """Test one- and two-dimensional input for Kraskov estimators."""
    expected_mi, src_one, s, target_one = _get_gauss_data(expand=False)
    src_two = np.expand_dims(src_one, axis=1)
    target_two = np.expand_dims(target_one, axis=1)
    ar_src_one, s = _get_ar_data(expand=False)
    ar_src_two = np.expand_dims(ar_src_one, axis=1)

    # MI
    mi_estimator = JidtKraskovMI(settings={})
    mi_cor_one = mi_estimator.estimate(src_one, target_one)
    _assert_result(mi_cor_one, expected_mi, 'JidtKraskovMI', 'MI')
    mi_cor_two = mi_estimator.estimate(src_two, target_two)
    _assert_result(mi_cor_two, expected_mi, 'JidtKraskovMI', 'MI')
    _compare_result(mi_cor_one, mi_cor_two,
                    'JidtKraskovMI one dim', 'JidtKraskovMI two dim', 'MI')
    # CMI
    cmi_estimator = JidtKraskovCMI(settings={})
    mi_cor_one = cmi_estimator.estimate(src_one, target_one)
    _assert_result(mi_cor_one, expected_mi, 'JidtKraskovCMI', 'CMI')
    mi_cor_two = cmi_estimator.estimate(src_two, target_two)
    _assert_result(mi_cor_two, expected_mi, 'JidtKraskovCMI', 'CMI')
    _compare_result(mi_cor_one, mi_cor_two,
                    'JidtKraskovMI one dim', 'JidtKraskovMI two dim', 'CMI')
    # TE
    te_estimator = JidtKraskovTE(settings={'history_target': 1})
    mi_cor_one = te_estimator.estimate(src_one[1:], target_one[:-1])
    _assert_result(mi_cor_one, expected_mi, 'JidtKraskovTE', 'TE')
    mi_cor_two = te_estimator.estimate(src_one[1:], target_one[:-1])
    _assert_result(mi_cor_two, expected_mi, 'JidtKraskovTE', 'TE')
    _compare_result(mi_cor_one, mi_cor_two,
                    'JidtKraskovMI one dim', 'JidtKraskovMI two dim', 'TE')
    # AIS
    ais_estimator = JidtKraskovAIS(settings={'history': 2})
    mi_cor_one = ais_estimator.estimate(ar_src_one)
    mi_cor_two = ais_estimator.estimate(ar_src_two)
    _compare_result(mi_cor_one, mi_cor_two,
                    'JidtKraskovAIS one dim', 'JidtKraskovAIS two dim',
                    'AIS (AR process)')
def test_te_gauss_data():
    """Test TE estimation on two sets of Gaussian random data.

    The first test is on correlated variables, the second on uncorrelated
    variables.

    Note that the calculation is based on a random variable (because the
    generated data is a set of random variables) - the result will be of the
    order of what we expect, but not exactly equal to it; in fact, there will
    be a large variance around it.
    """
    expected_mi, source1, source2, target = _get_gauss_data(expand=False)
    # add delay of one sample
    source1 = source1[1:]
    source2 = source2[1:]
    target = target[:-1]
    settings = {'discretise_method': 'equal',
                'n_discrete_bins': 4,
                'history_target': 1}
    # Test Kraskov
    mi_estimator = JidtKraskovTE(settings=settings)
    mi_cor = mi_estimator.estimate(source1, target)
    mi_uncor = mi_estimator.estimate(source2, target)
    _assert_result(mi_cor, expected_mi, 'JidtKraskovTE', 'TE (corr.)')
    _assert_result(mi_uncor, 0, 'JidtKraskovTE', 'TE (uncorr.)')

    # Test Gaussian
    mi_estimator = JidtGaussianTE(settings=settings)
    mi_cor = mi_estimator.estimate(source1, target)
    mi_uncor = mi_estimator.estimate(source2, target)
    _assert_result(mi_cor, expected_mi, 'JidtGaussianTE', 'TE (corr.)')
    _assert_result(mi_uncor, 0, 'JidtGaussianTE', 'TE (uncorr.)')

    # Test Discrete
    mi_estimator = JidtDiscreteTE(settings=settings)
    mi_cor = mi_estimator.estimate(source1, target)
    mi_uncor = mi_estimator.estimate(source2, target)
    _assert_result(mi_cor, expected_mi, 'JidtDiscreteTE', 'TE (corr.)')
    _assert_result(mi_uncor, 0, 'JidtDiscreteTE', 'TE (uncorr.)')
def test_invalid_settings_input():
    """Test handling of wrong inputs for settings dictionary."""

    # Wrong input type for settings dict.
    with pytest.raises(TypeError):
        JidtDiscreteMI(settings=1)
    with pytest.raises(TypeError):
        JidtDiscreteCMI(settings=1)
    with pytest.raises(TypeError):
        JidtDiscreteAIS(settings=1)
    with pytest.raises(TypeError):
        JidtDiscreteTE(settings=1)
    with pytest.raises(TypeError):
        JidtGaussianMI(settings=1)
    with pytest.raises(TypeError):
        JidtGaussianCMI(settings=1)
    with pytest.raises(TypeError):
        JidtGaussianAIS(settings=1)
    with pytest.raises(TypeError):
        JidtGaussianTE(settings=1)
    with pytest.raises(TypeError):
        JidtKraskovMI(settings=1)
    with pytest.raises(TypeError):
        JidtKraskovCMI(settings=1)
    with pytest.raises(TypeError):
        JidtKraskovAIS(settings=1)
    with pytest.raises(TypeError):
        JidtKraskovTE(settings=1)

    # Test if settings dict is initialised correctly.
    e = JidtDiscreteMI()
    assert type(
        e.settings) is dict, 'Did not initialise settings as dictionary.'
    e = JidtDiscreteCMI()
    assert type(
        e.settings) is dict, 'Did not initialise settings as dictionary.'
    e = JidtGaussianMI()
    assert type(
        e.settings) is dict, 'Did not initialise settings as dictionary.'
    e = JidtGaussianCMI()
    assert type(
        e.settings) is dict, 'Did not initialise settings as dictionary.'
    e = JidtKraskovMI()
    assert type(
        e.settings) is dict, 'Did not initialise settings as dictionary.'
    e = JidtKraskovCMI()
    assert type(
        e.settings) is dict, 'Did not initialise settings as dictionary.'

    # History parameter missing for AIS and TE estimation.
    with pytest.raises(RuntimeError):
        JidtDiscreteAIS(settings={})
    with pytest.raises(RuntimeError):
        JidtDiscreteTE(settings={})
    with pytest.raises(RuntimeError):
        JidtGaussianAIS(settings={})
    with pytest.raises(RuntimeError):
        JidtGaussianTE(settings={})
    with pytest.raises(RuntimeError):
        JidtKraskovAIS(settings={})
    with pytest.raises(RuntimeError):
        JidtKraskovTE(settings={})
def test_local_values():
    """Test estimation of local values and their return type."""
    expected_mi, source, s, target = _get_gauss_data(expand=False)
    ar_proc, s = _get_ar_data(expand=False)

    settings = {
        'discretise_method': 'equal',
        'num_discrete_bins': 4,
        'history_target': 1,
        'history': 2,
        'local_values': True
    }

    # MI - Discrete
    mi_estimator = JidtDiscreteMI(settings=settings)
    mi = mi_estimator.estimate(source, target)
    _assert_result(np.mean(mi), expected_mi, 'JidtDiscreteMI', 'MI')
    assert type(mi) is np.ndarray, 'Local values are not a numpy array.'

    # MI - Gaussian
    mi_estimator = JidtGaussianMI(settings=settings)
    mi = mi_estimator.estimate(source, target)
    _assert_result(np.mean(mi), expected_mi, 'JidtGaussianMI', 'MI')
    assert type(mi) is np.ndarray, 'Local values are not a numpy array.'

    # MI - Kraskov
    mi_estimator = JidtKraskovMI(settings=settings)
    mi = mi_estimator.estimate(source, target)
    _assert_result(np.mean(mi), expected_mi, 'JidtKraskovMI', 'MI')
    assert type(mi) is np.ndarray, 'Local values are not a numpy array.'

    # CMI - Discrete
    cmi_estimator = JidtDiscreteCMI(settings=settings)
    mi = cmi_estimator.estimate(source, target)
    _assert_result(np.mean(mi), expected_mi, 'JidtDiscreteCMI', 'CMI')
    assert type(mi) is np.ndarray, 'Local values are not a numpy array.'

    # MI - Gaussian
    mi_estimator = JidtGaussianCMI(settings=settings)
    mi = mi_estimator.estimate(source, target)
    _assert_result(np.mean(mi), expected_mi, 'JidtGaussianCMI', 'MI')
    assert type(mi) is np.ndarray, 'Local values are not a numpy array.'

    # MI - Kraskov
    mi_estimator = JidtKraskovCMI(settings=settings)
    mi = mi_estimator.estimate(source, target)
    _assert_result(np.mean(mi), expected_mi, 'JidtKraskovCMI', 'MI')
    assert type(mi) is np.ndarray, 'Local values are not a numpy array.'

    # TE - Discrete
    te_estimator = JidtDiscreteTE(settings=settings)
    mi = te_estimator.estimate(source[1:], target[:-1])
    _assert_result(np.mean(mi), expected_mi, 'JidtDiscreteTE', 'TE')
    assert type(mi) is np.ndarray, 'Local values are not a numpy array.'

    # TE - Gaussian
    mi_estimator = JidtGaussianTE(settings=settings)
    mi = mi_estimator.estimate(source[1:], target[:-1])
    _assert_result(np.mean(mi), expected_mi, 'JidtGaussianTE', 'MI')
    assert type(mi) is np.ndarray, 'Local values are not a numpy array.'

    # TE - Kraskov
    mi_estimator = JidtKraskovTE(settings=settings)
    mi = mi_estimator.estimate(source[1:], target[:-1])
    _assert_result(np.mean(mi), expected_mi, 'JidtKraskovTE', 'MI')
    assert type(mi) is np.ndarray, 'Local values are not a numpy array.'

    # AIS - Kraskov
    ais_estimator = JidtKraskovAIS(settings=settings)
    mi_k = ais_estimator.estimate(ar_proc)
    assert type(mi_k) is np.ndarray, 'Local values are not a numpy array.'

    # AIS - Discrete
    ais_estimator = JidtDiscreteAIS(settings=settings)
    mi_d = ais_estimator.estimate(ar_proc)
    assert type(mi_d) is np.ndarray, 'Local values are not a numpy array.'
    # TODO should we compare these?
    # _compare_result(np.mean(mi_k), np.mean(mi_d),
    #                 'JidtKraskovAIS', 'JidtDiscreteAIS', 'AIS (AR process)')

    # AIS - Gaussian
    ais_estimator = JidtGaussianAIS(settings=settings)
    mi_g = ais_estimator.estimate(ar_proc)
    assert type(mi_g) is np.ndarray, 'Local values are not a numpy array.'
    _compare_result(np.mean(mi_k), np.mean(mi_g), 'JidtKraskovAIS',
                    'JidtGaussianAIS', 'AIS (AR process)')
def test_insufficient_no_points():
    """Test if estimation aborts for too few data points."""
    expected_mi, source1, source2, target = _get_gauss_data(n=4)

    settings = {
        'kraskov_k': 4,
        'theiler_t': 0,
        'history': 1,
        'history_target': 1,
        'lag_mi': 1,
        'source_target_delay': 1}

    # Test first settings combination with k==N
    est = JidtKraskovTE(settings)
    with pytest.raises(RuntimeError): est.estimate(source1, target)
    est = JidtKraskovMI(settings)
    with pytest.raises(RuntimeError): est.estimate(source1, target)
    est = JidtKraskovCMI(settings)
    with pytest.raises(RuntimeError): est.estimate(source1, target, target)
    est = JidtKraskovAIS(settings)
    with pytest.raises(RuntimeError): est.estimate(source1)

    # Test a second combination with a Theiler-correction != 0
    settings['theiler_t'] = 1
    settings['kraskov_k'] = 2

    est = JidtKraskovTE(settings)
    with pytest.raises(RuntimeError): est.estimate(source1, target)
    est = JidtKraskovMI(settings)
    with pytest.raises(RuntimeError): est.estimate(source1, target)
    est = JidtKraskovCMI(settings)
    with pytest.raises(RuntimeError): est.estimate(source1, target, target)
    est = JidtKraskovAIS(settings)
    with pytest.raises(RuntimeError): est.estimate(source1)
Beispiel #7
0
def test_insufficient_no_points():
    """Test if estimation aborts for too few data points."""
    expected_mi, source1, source2, target = _get_gauss_data(n=4)

    settings = {
        'kraskov_k': 4,
        'theiler_t': 0,
        'history': 1,
        'history_target': 1,
        'lag_mi': 1,
        'source_target_delay': 1
    }

    # Test first settings combination with k==N
    est = JidtKraskovTE(settings)
    with pytest.raises(RuntimeError):
        est.estimate(source1, target)
    est = JidtKraskovMI(settings)
    with pytest.raises(RuntimeError):
        est.estimate(source1, target)
    est = JidtKraskovCMI(settings)
    with pytest.raises(RuntimeError):
        est.estimate(source1, target, target)
    est = JidtKraskovAIS(settings)
    with pytest.raises(RuntimeError):
        est.estimate(source1)

    # Test a second combination with a Theiler-correction != 0
    settings['theiler_t'] = 1
    settings['kraskov_k'] = 2

    est = JidtKraskovTE(settings)
    with pytest.raises(RuntimeError):
        est.estimate(source1, target)
    est = JidtKraskovMI(settings)
    with pytest.raises(RuntimeError):
        est.estimate(source1, target)
    est = JidtKraskovCMI(settings)
    with pytest.raises(RuntimeError):
        est.estimate(source1, target, target)
    est = JidtKraskovAIS(settings)
    with pytest.raises(RuntimeError):
        est.estimate(source1)
print('Estimated TE: {0:.5f}, expected TE: {1:.5f}'.format(te, expected_mi))
settings['history'] = 1
est = JidtDiscreteAIS(settings)
ais = est.estimate(target)
print('Estimated AIS: {0:.5f}, expected AIS: ~0'.format(ais))

# JIDT Kraskov estimators
settings = {}
est = JidtKraskovCMI(settings)
cmi = est.estimate(source_cor, target, source_uncor)
print('Estimated CMI: {0:.5f}, expected CMI: {1:.5f}'.format(cmi, expected_mi))
est = JidtKraskovMI(settings)
mi = est.estimate(source_cor, target)
print('Estimated MI: {0:.5f}, expected MI: {1:.5f}'.format(mi, expected_mi))
settings['history_target'] = 1
est = JidtKraskovTE(settings)
te = est.estimate(source_cor[1:n], target[0:n - 1])
print('Estimated TE: {0:.5f}, expected TE: {1:.5f}'.format(te, expected_mi))
settings['history'] = 1
est = JidtKraskovAIS(settings)
ais = est.estimate(target)
print('Estimated AIS: {0:.5f}, expected AIS: ~0'.format(ais))

# JIDT Gaussian estimators
settings = {}
est = JidtGaussianCMI(settings)
cmi = est.estimate(source_cor, target, source_uncor)
print('Estimated CMI: {0:.5f}, expected CMI: {1:.5f}'.format(cmi, expected_mi))
est = JidtGaussianMI(settings)
mi = est.estimate(source_cor, target)
print('Estimated MI: {0:.5f}, expected MI: {1:.5f}'.format(mi, expected_mi))