Exemplo n.º 1
0
def main():
    X, Y = toy.generate_crosses(n_samples=20, noise=5, n_crosses=1,
                                total_size=8)
    X_train, X_test, Y_train, Y_test = train_test_split(X, Y, test_size=.5)
    n_labels = len(np.unique(Y_train))
    crf = LatentGridCRF(n_labels=n_labels, n_states_per_label=[1, 2],
                        inference_method='lp')
    #clf = LatentSSVM(model=crf, max_iter=500, C=1000., verbose=2,
                     #check_constraints=True, n_jobs=-1, break_on_bad=True,
                     #base_svm='1-slack', inference_cache=20, tol=.1)
    clf = LatentSubgradientSSVM(
        model=crf, max_iter=500, C=1000., verbose=2,
        n_jobs=-1, learning_rate=0.1, show_loss_every=10)
    clf.fit(X_train, Y_train)

    #for X_, Y_, H, name in [[X_train, Y_train, clf.H_init_, "train"],
                            #[X_test, Y_test, [None] * len(X_test), "test"]]:
    for X_, Y_, H, name in [[X_train, Y_train, [None] * len(X_test), "train"],
                            [X_test, Y_test, [None] * len(X_test), "test"]]:
        Y_pred = clf.predict(X_)
        i = 0
        loss = 0
        for x, y, h_init, y_pred in zip(X_, Y_, H, Y_pred):
            loss += np.sum(y != y_pred)
            fig, ax = plt.subplots(3, 2)
            ax[0, 0].matshow(y, vmin=0, vmax=crf.n_labels - 1)
            ax[0, 0].set_title("ground truth")
            ax[0, 1].matshow(np.argmax(x, axis=-1),
                             vmin=0, vmax=crf.n_labels - 1)
            ax[0, 1].set_title("unaries only")
            if h_init is None:
                ax[1, 0].set_visible(False)
            else:
                ax[1, 0].matshow(h_init, vmin=0, vmax=crf.n_states - 1)
                ax[1, 0].set_title("latent initial")
            ax[1, 1].matshow(crf.latent(x, y, clf.w),
                             vmin=0, vmax=crf.n_states - 1)
            ax[1, 1].set_title("latent final")
            ax[2, 0].matshow(crf.inference(x, clf.w),
                             vmin=0, vmax=crf.n_states - 1)
            ax[2, 0].set_title("prediction latent")
            ax[2, 1].matshow(y_pred,
                             vmin=0, vmax=crf.n_labels - 1)
            ax[2, 1].set_title("prediction")
            for a in ax.ravel():
                a.set_xticks(())
                a.set_yticks(())
            fig.savefig("data_%s_%03d.png" % (name, i), bbox_inches="tight")
            i += 1
        print("loss %s set: %f" % (name, loss))
    print(clf.w)
def test_directional_bars():
    for inference_method in ['lp']:
        X, Y = toy.generate_easy(n_samples=10, noise=5, box_size=2,
                                 total_size=6, seed=1)
        n_labels = 2
        crf = LatentDirectionalGridCRF(n_labels=n_labels,
                                       n_states_per_label=[1, 4],
                                       inference_method=inference_method)
        clf = LatentSubgradientSSVM(model=crf, max_iter=500, C=10. ** 5,
                                    verbose=2)
        clf.fit(X, Y)
        Y_pred = clf.predict(X)

        assert_array_equal(np.array(Y_pred), Y)
def test_directional_bars():
    # this test is very fragile :-/
    X, Y = toy.generate_easy(n_samples=20, noise=2, box_size=2,
                             total_size=6, seed=2)
    n_labels = 2
    crf = LatentDirectionalGridCRF(n_labels=n_labels,
                                   n_states_per_label=[1, 4])
    clf = LatentSubgradientSSVM(model=crf, max_iter=75, C=10.,
                                learning_rate=1, momentum=0,
                                decay_exponent=0.5, decay_t0=10)
    clf.fit(X, Y)
    Y_pred = clf.predict(X)

    assert_array_equal(np.array(Y_pred), Y)
def test_with_crosses():
    # very simple dataset. k-means init is perfect
    for n_states_per_label in [2, [1, 2]]:
        # test with 2 states for both foreground and background,
        # as well as with single background state
        #for inference_method in ['ad3', 'qpbo', 'lp']:
        for inference_method in ['lp']:
            X, Y = toy.generate_crosses(n_samples=10, noise=5, n_crosses=1,
                                        total_size=8)
            n_labels = 2
            crf = LatentGridCRF(n_labels=n_labels,
                                n_states_per_label=n_states_per_label,
                                inference_method=inference_method)
            clf = LatentSubgradientSSVM(model=crf, max_iter=250, C=10. ** 5,
                                        verbose=20, learning_rate=0.0001,
                                        show_loss_every=10, momentum=0.98,
                                        decay_exponent=0)
            clf.fit(X, Y)
            Y_pred = clf.predict(X)
            assert_array_equal(np.array(Y_pred), Y)