Exemple #1
0
def test_kalman_pickle():
    kf = KalmanFilter(
        data.transition_matrix,
        data.observation_matrix,
        data.transition_covariance,
        data.observation_covariance,
        data.transition_offsets,
        data.observation_offset,
        data.initial_state_mean,
        data.initial_state_covariance,
        em_vars='all')

    # train and get log likelihood
    X = data.observations[0:10]
    kf = kf.em(X, n_iter=5)
    loglikelihood = kf.loglikelihood(X)

    # pickle Kalman Filter
    store = StringIO()
    pickle.dump(kf, store)
    clf = pickle.load(StringIO(store.getvalue()))

    # check that parameters came out already
    np.testing.assert_almost_equal(loglikelihood, kf.loglikelihood(X))

    # store it as BytesIO as well
    store = BytesIO()
    pickle.dump(kf, store)
    kf = pickle.load(BytesIO(store.getvalue()))
Exemple #2
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def test_kalman_fit():
    # check against MATLAB dataset
    kf = KalmanFilter(
        data.transition_matrix,
        data.observation_matrix,
        data.initial_transition_covariance,
        data.initial_observation_covariance,
        data.transition_offsets,
        data.observation_offset,
        data.initial_state_mean,
        data.initial_state_covariance,
        em_vars=['transition_covariance', 'observation_covariance'])

    loglikelihoods = np.zeros(5)
    for i in range(len(loglikelihoods)):
        loglikelihoods[i] = kf.loglikelihood(data.observations)
        kf.em(X=data.observations, n_iter=1)

    assert_true(np.allclose(loglikelihoods, data.loglikelihoods[:5]))

    # check that EM for all parameters is working
    kf.em_vars = 'all'
    n_timesteps = 30
    for i in range(len(loglikelihoods)):
        kf.em(X=data.observations[0:n_timesteps], n_iter=1)
        loglikelihoods[i] = kf.loglikelihood(data.observations[0:n_timesteps])
    for i in range(len(loglikelihoods) - 1):
        assert_true(loglikelihoods[i] < loglikelihoods[i + 1])