Python kernels.DotProduct方法代码示例

# 需要导入模块: from sklearn.gaussian_process import kernels [as 别名]
# 或者: from sklearn.gaussian_process.kernels import DotProduct [as 别名]
def test_gpr_correct_error_message():
    X = np.arange(12).reshape(6, -1)
    y = np.ones(6)
    kernel = DotProduct()
    gpr = GaussianProcessRegressor(kernel=kernel, alpha=0.0)
    assert_raise_message(np.linalg.LinAlgError,
                         "The kernel, %s, is not returning a "
                         "positive definite matrix. Try gradually increasing "
                         "the 'alpha' parameter of your "
                         "GaussianProcessRegressor estimator."
                         % kernel, gpr.fit, X, y) 

# 需要导入模块: from sklearn.gaussian_process import kernels [as 别名]
# 或者: from sklearn.gaussian_process.kernels import DotProduct [as 别名]
def test_learning(self):
        """General testing for catkit.learn"""
        with FingerprintDB(data_path) as fp:
            X = fp.get_fingerprints(params=np.arange(20) + 1)
            y = fp.get_fingerprints(params=['Ef']).T[0]

        X0, X1, y0, y1 = train_test_split(X, y, test_size=0.6, shuffle=True)

        kernel = DotProduct() + WhiteKernel()
        gp = GaussianProcessRegressor(
            kernel=kernel, optimizer=optimizer,
            n_restarts_optimizer=0, alpha=0)
        gp.fit(X0, y0)

        # This is an ugly way to define default properties
        # The 3rd argument is for a certain number of global
        # optimization steps using the basinhopping algorithm
        optimizer.__defaults__ = (True, 'L-BFGS-B', 3)

        gp = GaussianProcessRegressor(
            kernel=kernel, optimizer=optimizer,
            n_restarts_optimizer=0, alpha=0)
        gp.fit(X0, y0)

        samples = online_learning(
            X, y, [0, 1, 2], factors=[1, 1], nsteps=3, plot=True)

        test_array = np.array([0, 1, 2, 24, 15, 23])
        np.testing.assert_allclose(samples, test_array) 

# 需要导入模块: from sklearn.gaussian_process import kernels [as 别名]
# 或者: from sklearn.gaussian_process.kernels import DotProduct [as 别名]
def test_gp_regression_learner():
    df_train = pd.DataFrame({
        'id': ["id1", "id2", "id3", "id4"],
        'x1': [10.0, 13.0, 10.0, 13.0],
        "x2": [0, 1, 1, 0],
        'y': [2.3, 4.0, 100.0, -3.9]
    })

    df_test = pd.DataFrame({
        'id': ["id4", "id4", "id5", "id6"],
        'x1': [12.0, 1000.0, -4.0, 0.0],
        "x2": [1, 1, 0, 1],
        'y': [1.3, -4.0, 0.0, 49]
    })

    from sklearn.gaussian_process.kernels import RBF, WhiteKernel, DotProduct

    kernel = RBF() + WhiteKernel() + DotProduct()

    learner = gp_regression_learner(features=["x1", "x2"],
                                    target="y",
                                    kernel=kernel,
                                    alpha=0.1,
                                    extra_variance="fit",
                                    return_std=True,
                                    extra_params=None,
                                    prediction_column="prediction")

    predict_fn, pred_train, log = learner(df_train)

    pred_test = predict_fn(df_test)

    expected_col_train = df_train.columns.tolist() + ["prediction", "prediction_std"]
    expected_col_test = df_test.columns.tolist() + ["prediction", "prediction_std"]

    assert Counter(expected_col_train) == Counter(pred_train.columns.tolist())
    assert Counter(expected_col_test) == Counter(pred_test.columns.tolist())
    assert (pred_test.columns == pred_train.columns).all()
    assert "prediction" in pred_test.columns 

# 需要导入模块: from sklearn.gaussian_process import kernels [as 别名]
# 或者: from sklearn.gaussian_process.kernels import DotProduct [as 别名]
def online_learning(X, y, samples, factors=[1.0, 1.0], nsteps=40, plot=False):
    """A simple utility for performing online learning. The main
    components required are a regression method and a scoring
    technique.

    Currently, the scoring methodology and regressor are baked in.
    These need to be made modular.

    Minimum 3 samples are required for 3 fold cross validation.
    """
    ids = np.arange(len(y))

    kernel = DotProduct() + WhiteKernel()
    regressor = GaussianProcessRegressor(
        kernel=kernel, n_restarts_optimizer=5, alpha=0)

    step = 0
    while step < nsteps:
        X0 = X[samples]
        y0 = y[samples]

        regressor.fit(X0, y0)
        yp, ys = regressor.predict(X, return_std=True)

        # Provides some form of normalization.
        # Multiples denote relative importance
        yp_scale = preprocessing.scale(yp) * factors[0]
        ys_scale = preprocessing.scale(ys) * factors[1]
        score = ys_scale - yp_scale
        srt = np.argsort(score)[::-1]

        for s in srt:
            if s not in samples:
                samples = np.concatenate([samples, [s]])
                break

        if plot:
            mae = np.round(mean_absolute_error(yp, y), 3)
            n = len(samples)

            fig, ax = plt.subplots(figsize=(6, 4))
            ax.plot(ids, y, 'o', zorder=0)
            ax.errorbar(ids, yp, yerr=ys, fmt='o', zorder=1)
            ax.plot(samples, y[samples], 'o', zorder=3)
            xlim = ax.get_xlim()
            ylim = ax.get_ylim()
            ax.text(xlim[0] / 9.0, ylim[0] / 9.0, mae)
            plt.tight_layout()
            plt.savefig('./online-learning-RBF-{}.png'.format(n))
            plt.close()

        step += 1

    return samples