Example #1
0
def test_linearsvx_loss_penalty_deprecations():
    X, y = [[0.0], [1.0]], [0, 1]

    msg = ("loss='%s' has been deprecated in favor of "
           "loss='%s' as of 0.16. Backward compatibility"
           " for the %s will be removed in %s")

    # LinearSVC
    # loss l1 --> hinge
    assert_warns_message(FutureWarning,
                         msg % ("l1", "hinge", "loss='l1'", "0.23"),
                         svm.LinearSVC(loss="l1").fit, X, y)

    # loss l2 --> squared_hinge
    assert_warns_message(FutureWarning,
                         msg % ("l2", "squared_hinge", "loss='l2'", "0.23"),
                         svm.LinearSVC(loss="l2").fit, X, y)

    # LinearSVR
    # loss l1 --> epsilon_insensitive
    assert_warns_message(
        FutureWarning,
        msg % ("l1", "epsilon_insensitive", "loss='l1'", "0.23"),
        svm.LinearSVR(loss="l1").fit, X, y)

    # loss l2 --> squared_epsilon_insensitive
    assert_warns_message(
        FutureWarning,
        msg % ("l2", "squared_epsilon_insensitive", "loss='l2'", "0.23"),
        svm.LinearSVR(loss="l2").fit, X, y)
Example #2
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def test_svr():
    # Test Support Vector Regression

    diabetes = datasets.load_diabetes()
    for clf in (svm.NuSVR(kernel='linear', nu=.4,
                          C=1.0), svm.NuSVR(kernel='linear', nu=.4, C=10.),
                svm.SVR(kernel='linear',
                        C=10.), svm.LinearSVR(C=10.), svm.LinearSVR(C=10.)):
        clf.fit(diabetes.data, diabetes.target)
        assert clf.score(diabetes.data, diabetes.target) > 0.02

    # non-regression test; previously, BaseLibSVM would check that
    # len(np.unique(y)) < 2, which must only be done for SVC
    svm.SVR().fit(diabetes.data, np.ones(len(diabetes.data)))
    svm.LinearSVR().fit(diabetes.data, np.ones(len(diabetes.data)))
Example #3
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def test_linear_svm_convergence_warnings():
    # Test that warnings are raised if model does not converge

    lsvc = svm.LinearSVC(random_state=0, max_iter=2)
    assert_warns(ConvergenceWarning, lsvc.fit, X, Y)
    assert lsvc.n_iter_ == 2

    lsvr = svm.LinearSVR(random_state=0, max_iter=2)
    assert_warns(ConvergenceWarning, lsvr.fit, iris.data, iris.target)
    assert lsvr.n_iter_ == 2
Example #4
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def test_linearsvr_fit_sampleweight():
    # check correct result when sample_weight is 1
    # check that SVR(kernel='linear') and LinearSVC() give
    # comparable results
    diabetes = datasets.load_diabetes()
    n_samples = len(diabetes.target)
    unit_weight = np.ones(n_samples)
    lsvr = svm.LinearSVR(C=1e3, tol=1e-12,
                         max_iter=10000).fit(diabetes.data,
                                             diabetes.target,
                                             sample_weight=unit_weight)
    score1 = lsvr.score(diabetes.data, diabetes.target)

    lsvr_no_weight = svm.LinearSVR(C=1e3, tol=1e-12,
                                   max_iter=10000).fit(diabetes.data,
                                                       diabetes.target)
    score2 = lsvr_no_weight.score(diabetes.data, diabetes.target)

    assert_allclose(np.linalg.norm(lsvr.coef_),
                    np.linalg.norm(lsvr_no_weight.coef_), 1, 0.0001)
    assert_almost_equal(score1, score2, 2)

    # check that fit(X)  = fit([X1, X2, X3],sample_weight = [n1, n2, n3]) where
    # X = X1 repeated n1 times, X2 repeated n2 times and so forth
    random_state = check_random_state(0)
    random_weight = random_state.randint(0, 10, n_samples)
    lsvr_unflat = svm.LinearSVR(C=1e3, tol=1e-12, max_iter=10000).fit(
        diabetes.data, diabetes.target, sample_weight=random_weight)
    score3 = lsvr_unflat.score(diabetes.data,
                               diabetes.target,
                               sample_weight=random_weight)

    X_flat = np.repeat(diabetes.data, random_weight, axis=0)
    y_flat = np.repeat(diabetes.target, random_weight, axis=0)
    lsvr_flat = svm.LinearSVR(C=1e3, tol=1e-12,
                              max_iter=10000).fit(X_flat, y_flat)
    score4 = lsvr_flat.score(X_flat, y_flat)

    assert_almost_equal(score3, score4, 2)
Example #5
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def test_linearsvr():
    # check that SVR(kernel='linear') and LinearSVC() give
    # comparable results
    diabetes = datasets.load_diabetes()
    lsvr = svm.LinearSVR(C=1e3).fit(diabetes.data, diabetes.target)
    score1 = lsvr.score(diabetes.data, diabetes.target)

    svr = svm.SVR(kernel='linear', C=1e3).fit(diabetes.data, diabetes.target)
    score2 = svr.score(diabetes.data, diabetes.target)

    assert_allclose(np.linalg.norm(lsvr.coef_), np.linalg.norm(svr.coef_), 1,
                    0.0001)
    assert_almost_equal(score1, score2, 2)
Example #6
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def test_svr_coef_sign():
    # Test that SVR(kernel="linear") has coef_ with the right sign.
    # Non-regression test for #2933.
    X = np.random.RandomState(21).randn(10, 3)
    y = np.random.RandomState(12).randn(10)

    for svr in [
            svm.SVR(kernel='linear'),
            svm.NuSVR(kernel='linear'),
            svm.LinearSVR()
    ]:
        svr.fit(X, y)
        assert_array_almost_equal(
            svr.predict(X),
            np.dot(X, svr.coef_.ravel()) + svr.intercept_)