コード例 #1
0
def test_log_marg_k():

    np.random.seed(1)

    # Generate data
    D = 10
    N_1 = 10
    X_1 = 5 * np.random.rand(N_1, D) - 1

    # Prior
    m_0 = 5 * np.random.rand(D) - 2
    k_0 = np.random.randint(15)
    v_0 = D + np.random.randint(5)
    S_0 = 2 * np.random.rand(D) + 3
    prior = NIW(m_0=m_0, k_0=k_0, v_0=v_0, S_0=S_0)

    # Setup GMM
    assignments = np.concatenate([np.zeros(N_1)])
    gmm = GaussianComponentsDiag(X_1, prior, assignments=assignments)

    # Calculate marginal for component by hand
    k_N = k_0 + N_1
    v_N = v_0 + N_1
    m_N = (k_0 * m_0 + N_1 * X_1.mean(axis=0)) / k_N
    S_N = S_0 + np.square(X_1).sum(
        axis=0) + k_0 * np.square(m_0) - k_N * np.square(m_N)
    var = S_N * (k_N + 1) / (k_N * v_N)
    expected_log_marg = (-N_1 * D / 2. * math.log(np.pi) +
                         D / 2. * math.log(k_0) - D / 2. * math.log(k_N) +
                         v_0 / 2. * np.log(S_0).sum() -
                         v_N / 2. * np.log(S_N).sum() + D *
                         (gammaln(v_N / 2.) - gammaln(v_0 / 2.)))

    npt.assert_almost_equal(gmm.log_marg_k(0), expected_log_marg)
コード例 #2
0
def test_log_post_pred_k():

    np.random.seed(1)

    # Prior
    D = 10
    m_0 = 5 * np.random.rand(D) - 2
    k_0 = np.random.randint(15)
    v_0 = D + np.random.randint(5)
    S_0 = 2 * np.random.rand(D) + 3
    prior = NIW(m_0=m_0, k_0=k_0, v_0=v_0, S_0=S_0)

    # Data
    N = 12
    X = 5 * np.random.rand(N, D) - 1

    # Setup GMM
    gmm = GaussianComponentsDiag(X, prior)
    for i in range(N):
        gmm.add_item(i, 0)

    # Calculate posterior by hand
    x = X[0]
    k_N = k_0 + N
    v_N = v_0 + N
    m_N = (k_0 * m_0 + N * X[:N].mean(axis=0)) / k_N
    S_N = S_0 + np.square(
        X[:N]).sum(axis=0) + k_0 * np.square(m_0) - k_N * np.square(m_N)
    var = S_N * (k_N + 1) / (k_N * v_N)
    expected_posterior = np.sum([
        students_t(x[i], m_N[i], S_N[i] * (k_N + 1) / (k_N * v_N), v_N)
        for i in range(len(x))
    ])

    npt.assert_almost_equal(gmm.log_post_pred_k(0, 0), expected_posterior)
コード例 #3
0
def test_log_post_pred_k():

    np.random.seed(1)

    # Prior
    D = 10
    m_0 = 5*np.random.rand(D) - 2
    k_0 = np.random.randint(15)
    v_0 = D + np.random.randint(5)
    S_0 = 2*np.random.rand(D) + 3
    prior = NIW(m_0=m_0, k_0=k_0, v_0=v_0, S_0=S_0)

    # Data
    N = 12
    X = 5*np.random.rand(N, D) - 1

    # Setup GMM
    gmm = GaussianComponentsDiag(X, prior)
    for i in range(N):
        gmm.add_item(i, 0)

    # Calculate posterior by hand
    x = X[0]
    k_N = k_0 + N
    v_N = v_0 + N
    m_N = (k_0*m_0 + N*X[:N].mean(axis=0))/k_N
    S_N = S_0 + np.square(X[:N]).sum(axis=0) + k_0*np.square(m_0) - k_N*np.square(m_N)
    var = S_N*(k_N + 1)/(k_N*v_N)
    expected_posterior = np.sum(
        [students_t(x[i], m_N[i], S_N[i]*(k_N + 1)/(k_N*v_N), v_N) for i in range(len(x))]
        )

    npt.assert_almost_equal(gmm.log_post_pred_k(0, 0), expected_posterior)
コード例 #4
0
def test_log_post_pred():

    # Data generated with np.random.seed(2); np.random.rand(11, 4)
    X = np.array([[0.4359949, 0.02592623, 0.54966248, 0.43532239],
                  [0.4203678, 0.33033482, 0.20464863, 0.61927097],
                  [0.29965467, 0.26682728, 0.62113383, 0.52914209],
                  [0.13457995, 0.51357812, 0.18443987, 0.78533515],
                  [0.85397529, 0.49423684, 0.84656149, 0.07964548],
                  [0.50524609, 0.0652865, 0.42812233, 0.09653092],
                  [0.12715997, 0.59674531, 0.226012, 0.10694568],
                  [0.22030621, 0.34982629, 0.46778748, 0.20174323],
                  [0.64040673, 0.48306984, 0.50523672, 0.38689265],
                  [0.79363745, 0.58000418, 0.1622986, 0.70075235],
                  [0.96455108, 0.50000836, 0.88952006, 0.34161365]])
    N, D = X.shape

    # Setup densities
    m_0 = X.mean(axis=0)
    k_0 = 0.05
    v_0 = D + 10
    S_0 = 0.5 * np.ones(D)
    prior = NIW(m_0, k_0, v_0, S_0)
    gmm = GaussianComponentsDiag(X, prior, [0, 0, 0, 1, 0, 1, 3, 4, 3, 2, -1])
    expected_log_post_pred = log_post_pred_unvectorized(gmm, 10)

    npt.assert_almost_equal(gmm.log_post_pred(10), expected_log_post_pred)
コード例 #5
0
def test_log_marg_k():

    np.random.seed(1)

    # Generate data
    D = 10
    N_1 = 10
    X_1 = 5*np.random.rand(N_1, D) - 1

    # Prior
    m_0 = 5*np.random.rand(D) - 2
    k_0 = np.random.randint(15)
    v_0 = D + np.random.randint(5)
    S_0 = 2*np.random.rand(D) + 3
    prior = NIW(m_0=m_0, k_0=k_0, v_0=v_0, S_0=S_0)

    # Setup GMM
    assignments = np.concatenate([np.zeros(N_1)])
    gmm = GaussianComponentsDiag(X_1, prior, assignments=assignments)

    # Calculate marginal for component by hand
    k_N = k_0 + N_1
    v_N = v_0 + N_1
    m_N = (k_0*m_0 + N_1*X_1.mean(axis=0))/k_N
    S_N = S_0 + np.square(X_1).sum(axis=0) + k_0*np.square(m_0) - k_N*np.square(m_N)
    var = S_N*(k_N + 1)/(k_N*v_N)
    expected_log_marg = (
        - N_1*D/2.*math.log(np.pi)
        + D/2.*math.log(k_0) - D/2.*math.log(k_N)
        + v_0/2.*np.log(S_0).sum() - v_N/2.*np.log(S_N).sum()
        + D*(gammaln(v_N/2.) - gammaln(v_0/2.))
        )

    npt.assert_almost_equal(gmm.log_marg_k(0), expected_log_marg)
コード例 #6
0
def test_log_post_pred():

    # Data generated with np.random.seed(2); np.random.rand(11, 4)
    X = np.array([
        [ 0.4359949 ,  0.02592623,  0.54966248,  0.43532239],
        [ 0.4203678 ,  0.33033482,  0.20464863,  0.61927097],
        [ 0.29965467,  0.26682728,  0.62113383,  0.52914209],
        [ 0.13457995,  0.51357812,  0.18443987,  0.78533515],
        [ 0.85397529,  0.49423684,  0.84656149,  0.07964548],
        [ 0.50524609,  0.0652865 ,  0.42812233,  0.09653092],
        [ 0.12715997,  0.59674531,  0.226012  ,  0.10694568],
        [ 0.22030621,  0.34982629,  0.46778748,  0.20174323],
        [ 0.64040673,  0.48306984,  0.50523672,  0.38689265],
        [ 0.79363745,  0.58000418,  0.1622986 ,  0.70075235],
        [ 0.96455108,  0.50000836,  0.88952006,  0.34161365]
        ])
    N, D = X.shape

    # Setup densities
    m_0 = X.mean(axis=0)
    k_0 = 0.05
    v_0 = D + 10
    S_0 = 0.5*np.ones(D)
    prior = NIW(m_0, k_0, v_0, S_0)
    gmm = GaussianComponentsDiag(X, prior, [0, 0, 0, 1, 0, 1, 3, 4, 3, 2, -1])
    expected_log_post_pred = log_post_pred_unvectorized(gmm, 10)

    npt.assert_almost_equal(gmm.log_post_pred(10), expected_log_post_pred)
コード例 #7
0
def test_3component_with_delete_post_pred_k():

    np.random.seed(1)

    # Generate data
    D = 10
    N_1 = 10
    N_2 = 5
    N_3 = 5
    X = 5*np.random.rand(N_1 + N_2 + N_3, D) - 1
    X_1 = X[:N_1]
    X_2 = X[N_1:N_1 + N_2]
    X_3 = X[N_1 + N_2:]

    # Prior
    m_0 = 5*np.random.rand(D) - 2
    k_0 = np.random.randint(15)
    v_0 = D + np.random.randint(5)
    S_0 = 2*np.random.rand(D) + 3
    prior = NIW(m_0=m_0, k_0=k_0, v_0=v_0, S_0=S_0)

    # Setup GMM
    assignments = np.concatenate([np.zeros(N_1), np.ones(N_2), 2*np.ones(N_3)])
    gmm = GaussianComponentsDiag(X, prior, assignments=assignments)

    # Remove everything from component 2
    for i in range(N_1, N_1 + N_2):
        gmm.del_item(i)

    # Calculate posterior for first component by hand
    x_1 = X_1[0]
    k_N = k_0 + N_1
    v_N = v_0 + N_1
    m_N = (k_0*m_0 + N_1*X_1.mean(axis=0))/k_N
    S_N = S_0 + np.square(X_1).sum(axis=0) + k_0*np.square(m_0) - k_N*np.square(m_N)
    var = S_N*(k_N + 1)/(k_N*v_N)
    expected_posterior = np.sum(
        [students_t(x_1[i], m_N[i], S_N[i]*(k_N + 1)/(k_N*v_N), v_N) for i in range(len(x_1))]
        )

    npt.assert_almost_equal(gmm.log_post_pred_k(0, 0), expected_posterior)

    # Calculate posterior for second component by hand
    x_1 = X_3[0]
    k_N = k_0 + N_3
    v_N = v_0 + N_3
    m_N = (k_0*m_0 + N_3*X_3.mean(axis=0))/k_N
    S_N = S_0 + np.square(X_3).sum(axis=0) + k_0*np.square(m_0) - k_N*np.square(m_N)
    var = S_N*(k_N + 1)/(k_N*v_N)
    expected_posterior = np.sum(
        [students_t(x_1[i], m_N[i], S_N[i]*(k_N + 1)/(k_N*v_N), v_N) for i in range(len(x_1))]
        )

    npt.assert_almost_equal(gmm.log_post_pred_k(N_1 + N_2, 1), expected_posterior)
コード例 #8
0
def test_2component_post_pred_k():

    np.random.seed(1)

    # Generate data
    D = 10
    N_1 = 10
    N_2 = 5
    X = 5*np.random.rand(N_1 + N_2, D) - 1
    X_1 = X[:N_1]
    X_2 = X[N_1:]

    # Prior
    m_0 = 5*np.random.rand(D) - 2
    k_0 = np.random.randint(15)
    v_0 = D + np.random.randint(5)
    S_0 = 2*np.random.rand(D) + 3
    prior = NIW(m_0=m_0, k_0=k_0, v_0=v_0, S_0=S_0)

    # Setup GMM
    assignments = np.concatenate([np.zeros(N_1), np.ones(N_2)])
    gmm = GaussianComponentsDiag(X, prior, assignments=assignments)

    # Remove one item (as additional check)
    gmm.del_item(N_1 + N_2 - 1)
    X_2 = X_2[:-1]
    N_2 -= 1

    # Calculate posterior for first component by hand
    x_1 = X_1[0]
    k_N = k_0 + N_1
    v_N = v_0 + N_1
    m_N = (k_0*m_0 + N_1*X_1.mean(axis=0))/k_N
    S_N = S_0 + np.square(X_1).sum(axis=0) + k_0*np.square(m_0) - k_N*np.square(m_N)
    var = S_N*(k_N + 1)/(k_N*v_N)
    expected_posterior = np.sum(
        [students_t(x_1[i], m_N[i], S_N[i]*(k_N + 1)/(k_N*v_N), v_N) for i in range(len(x_1))]
        )

    npt.assert_almost_equal(gmm.log_post_pred_k(0, 0), expected_posterior)

    # Calculate posterior for second component by hand
    x_1 = X_2[0]
    k_N = k_0 + N_2
    v_N = v_0 + N_2
    m_N = (k_0*m_0 + N_2*X_2.mean(axis=0))/k_N
    S_N = S_0 + np.square(X_2).sum(axis=0) + k_0*np.square(m_0) - k_N*np.square(m_N)
    var = S_N*(k_N + 1)/(k_N*v_N)
    expected_posterior = np.sum(
        [students_t(x_1[i], m_N[i], S_N[i]*(k_N + 1)/(k_N*v_N), v_N) for i in range(len(x_1))]
        )

    npt.assert_almost_equal(gmm.log_post_pred_k(N_1, 1), expected_posterior)
コード例 #9
0
def test_log_prod_students_t():

    np.random.seed(1)

    # Prior
    D = 10
    m_0 = 5*np.random.rand(D) - 2
    k_0 = np.random.randint(15)
    v_0 = D + np.random.randint(5)
    S_0 = 2*np.random.rand(D) + 3
    prior = NIW(m_0=m_0, k_0=k_0, v_0=v_0, S_0=S_0)

    # GMM we will use to access `_log_prod_students_t`
    x = 3*np.random.rand(D) + 4
    gmm = GaussianComponentsDiag(np.array([x]), prior)

    expected_prior = np.sum(
        [students_t(x[i], m_0[i], S_0[i]*(k_0 + 1)/(k_0 * v_0), v_0) for i in range(len(x))]
        )

    npt.assert_almost_equal(gmm.log_prior(0), expected_prior)
コード例 #10
0
def test_3component_with_delete_post_pred_k():

    np.random.seed(1)

    # Generate data
    D = 10
    N_1 = 10
    N_2 = 5
    N_3 = 5
    X = 5 * np.random.rand(N_1 + N_2 + N_3, D) - 1
    X_1 = X[:N_1]
    X_2 = X[N_1:N_1 + N_2]
    X_3 = X[N_1 + N_2:]

    # Prior
    m_0 = 5 * np.random.rand(D) - 2
    k_0 = np.random.randint(15)
    v_0 = D + np.random.randint(5)
    S_0 = 2 * np.random.rand(D) + 3
    prior = NIW(m_0=m_0, k_0=k_0, v_0=v_0, S_0=S_0)

    # Setup GMM
    assignments = np.concatenate(
        [np.zeros(N_1), np.ones(N_2), 2 * np.ones(N_3)])
    gmm = GaussianComponentsDiag(X, prior, assignments=assignments)

    # Remove everything from component 2
    for i in range(N_1, N_1 + N_2):
        gmm.del_item(i)

    # Calculate posterior for first component by hand
    x_1 = X_1[0]
    k_N = k_0 + N_1
    v_N = v_0 + N_1
    m_N = (k_0 * m_0 + N_1 * X_1.mean(axis=0)) / k_N
    S_N = S_0 + np.square(X_1).sum(
        axis=0) + k_0 * np.square(m_0) - k_N * np.square(m_N)
    var = S_N * (k_N + 1) / (k_N * v_N)
    expected_posterior = np.sum([
        students_t(x_1[i], m_N[i], S_N[i] * (k_N + 1) / (k_N * v_N), v_N)
        for i in range(len(x_1))
    ])

    npt.assert_almost_equal(gmm.log_post_pred_k(0, 0), expected_posterior)

    # Calculate posterior for second component by hand
    x_1 = X_3[0]
    k_N = k_0 + N_3
    v_N = v_0 + N_3
    m_N = (k_0 * m_0 + N_3 * X_3.mean(axis=0)) / k_N
    S_N = S_0 + np.square(X_3).sum(
        axis=0) + k_0 * np.square(m_0) - k_N * np.square(m_N)
    var = S_N * (k_N + 1) / (k_N * v_N)
    expected_posterior = np.sum([
        students_t(x_1[i], m_N[i], S_N[i] * (k_N + 1) / (k_N * v_N), v_N)
        for i in range(len(x_1))
    ])

    npt.assert_almost_equal(gmm.log_post_pred_k(N_1 + N_2, 1),
                            expected_posterior)
コード例 #11
0
def test_log_prod_students_t():

    np.random.seed(1)

    # Prior
    D = 10
    m_0 = 5 * np.random.rand(D) - 2
    k_0 = np.random.randint(15)
    v_0 = D + np.random.randint(5)
    S_0 = 2 * np.random.rand(D) + 3
    prior = NIW(m_0=m_0, k_0=k_0, v_0=v_0, S_0=S_0)

    # GMM we will use to access `_log_prod_students_t`
    x = 3 * np.random.rand(D) + 4
    gmm = GaussianComponentsDiag(np.array([x]), prior)

    expected_prior = np.sum([
        students_t(x[i], m_0[i], S_0[i] * (k_0 + 1) / (k_0 * v_0), v_0)
        for i in range(len(x))
    ])

    npt.assert_almost_equal(gmm.log_prior(0), expected_prior)
コード例 #12
0
def test_2component_post_pred_k():

    np.random.seed(1)

    # Generate data
    D = 10
    N_1 = 10
    N_2 = 5
    X = 5 * np.random.rand(N_1 + N_2, D) - 1
    X_1 = X[:N_1]
    X_2 = X[N_1:]

    # Prior
    m_0 = 5 * np.random.rand(D) - 2
    k_0 = np.random.randint(15)
    v_0 = D + np.random.randint(5)
    S_0 = 2 * np.random.rand(D) + 3
    prior = NIW(m_0=m_0, k_0=k_0, v_0=v_0, S_0=S_0)

    # Setup GMM
    assignments = np.concatenate([np.zeros(N_1), np.ones(N_2)])
    gmm = GaussianComponentsDiag(X, prior, assignments=assignments)

    # Remove one item (as additional check)
    gmm.del_item(N_1 + N_2 - 1)
    X_2 = X_2[:-1]
    N_2 -= 1

    # Calculate posterior for first component by hand
    x_1 = X_1[0]
    k_N = k_0 + N_1
    v_N = v_0 + N_1
    m_N = (k_0 * m_0 + N_1 * X_1.mean(axis=0)) / k_N
    S_N = S_0 + np.square(X_1).sum(
        axis=0) + k_0 * np.square(m_0) - k_N * np.square(m_N)
    var = S_N * (k_N + 1) / (k_N * v_N)
    expected_posterior = np.sum([
        students_t(x_1[i], m_N[i], S_N[i] * (k_N + 1) / (k_N * v_N), v_N)
        for i in range(len(x_1))
    ])

    npt.assert_almost_equal(gmm.log_post_pred_k(0, 0), expected_posterior)

    # Calculate posterior for second component by hand
    x_1 = X_2[0]
    k_N = k_0 + N_2
    v_N = v_0 + N_2
    m_N = (k_0 * m_0 + N_2 * X_2.mean(axis=0)) / k_N
    S_N = S_0 + np.square(X_2).sum(
        axis=0) + k_0 * np.square(m_0) - k_N * np.square(m_N)
    var = S_N * (k_N + 1) / (k_N * v_N)
    expected_posterior = np.sum([
        students_t(x_1[i], m_N[i], S_N[i] * (k_N + 1) / (k_N * v_N), v_N)
        for i in range(len(x_1))
    ])

    npt.assert_almost_equal(gmm.log_post_pred_k(N_1, 1), expected_posterior)
コード例 #13
0
def test_del_item():

    np.random.seed(1)

    # Prior
    D = 10
    m_0 = 5 * np.random.rand(D) - 2
    k_0 = np.random.randint(15)
    v_0 = D + np.random.randint(5)
    S_0 = 2 * np.random.rand(D) + 3
    prior = NIW(m_0=m_0, k_0=k_0, v_0=v_0, S_0=S_0)

    # Data
    N = 12
    X = 5 * np.random.rand(N, D) - 1

    # Setup GMM
    gmm = GaussianComponentsDiag(X, prior)
    for i in range(N):
        gmm.add_item(i, 0)

    # Remove 5 random items
    del_items = set(np.random.randint(1, N, size=5))
    for i in del_items:
        gmm.del_item(i)
    indices = list(set(range(N)).difference(del_items))

    # Calculate posterior by hand
    X = X[indices]
    N, _ = X.shape
    x = X[0]
    k_N = k_0 + N
    v_N = v_0 + N
    m_N = (k_0 * m_0 + N * X[:N].mean(axis=0)) / k_N
    S_N = S_0 + np.square(
        X[:N]).sum(axis=0) + k_0 * np.square(m_0) - k_N * np.square(m_N)
    var = S_N * (k_N + 1) / (k_N * v_N)
    expected_posterior = np.sum([
        students_t(x[i], m_N[i], S_N[i] * (k_N + 1) / (k_N * v_N), v_N)
        for i in range(len(x))
    ])

    npt.assert_almost_equal(gmm.log_post_pred_k(0, 0), expected_posterior)
コード例 #14
0
def test_del_item():

    np.random.seed(1)

    # Prior
    D = 10
    m_0 = 5*np.random.rand(D) - 2
    k_0 = np.random.randint(15)
    v_0 = D + np.random.randint(5)
    S_0 = 2*np.random.rand(D) + 3
    prior = NIW(m_0=m_0, k_0=k_0, v_0=v_0, S_0=S_0)

    # Data
    N = 12
    X = 5*np.random.rand(N, D) - 1

    # Setup GMM
    gmm = GaussianComponentsDiag(X, prior)
    for i in range(N):
        gmm.add_item(i, 0)

    # Remove 5 random items
    del_items = set(np.random.randint(1, N, size=5))
    for i in del_items:
        gmm.del_item(i)
    indices = list(set(range(N)).difference(del_items))

    # Calculate posterior by hand
    X = X[indices]
    N, _ = X.shape
    x = X[0]
    k_N = k_0 + N
    v_N = v_0 + N
    m_N = (k_0*m_0 + N*X[:N].mean(axis=0))/k_N
    S_N = S_0 + np.square(X[:N]).sum(axis=0) + k_0*np.square(m_0) - k_N*np.square(m_N)
    var = S_N*(k_N + 1)/(k_N*v_N)
    expected_posterior = np.sum(
        [students_t(x[i], m_N[i], S_N[i]*(k_N + 1)/(k_N*v_N), v_N) for i in range(len(x))]
        )

    npt.assert_almost_equal(gmm.log_post_pred_k(0, 0), expected_posterior)