Пример #1
0
def test_constraint_removal():
    digits = load_digits()
    X, y = digits.data, digits.target
    y = 2 * (y % 2) - 1  # even vs odd as +1 vs -1
    X = X / 16.
    pbl = BinaryClf(n_features=X.shape[1])
    clf_no_removal = OneSlackSSVM(model=pbl, max_iter=500, C=1,
                                  inactive_window=0, tol=0.01)
    clf_no_removal.fit(X, y)
    clf = OneSlackSSVM(model=pbl, max_iter=500, C=1, tol=0.01,
                       inactive_threshold=1e-8)
    clf.fit(X, y)
    # check that we learned something
    assert_greater(clf.score(X, y), .92)

    # results are mostly equal
    # if we decrease tol, they will get more similar
    assert_less(np.mean(clf.predict(X) != clf_no_removal.predict(X)), 0.02)

    # without removal, have as many constraints as iterations
    assert_equal(len(clf_no_removal.objective_curve_),
                 len(clf_no_removal.constraints_))

    # with removal, there are less constraints than iterations
    assert_less(len(clf.constraints_),
                len(clf.objective_curve_))
Пример #2
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def test_standard_svm_blobs_2d_class_weight():
    # no edges, reduce to crammer-singer svm
    X, Y = make_blobs(n_samples=210, centers=3, random_state=1, cluster_std=3,
                      shuffle=False)
    X = np.hstack([X, np.ones((X.shape[0], 1))])
    X, Y = X[:170], Y[:170]

    X_graphs = [(x[np.newaxis, :], np.empty((0, 2), dtype=np.int)) for x in X]

    pbl = GraphCRF(n_features=3, n_states=3, inference_method='unary')
    svm = OneSlackSSVM(pbl, check_constraints=False, C=1000)

    svm.fit(X_graphs, Y[:, np.newaxis])

    weights = 1. / np.bincount(Y)
    weights *= len(weights) / np.sum(weights)

    pbl_class_weight = GraphCRF(n_features=3, n_states=3, class_weight=weights,
                                inference_method='unary')
    svm_class_weight = OneSlackSSVM(pbl_class_weight, C=10,
                                    check_constraints=False,
                                    break_on_bad=False)
    svm_class_weight.fit(X_graphs, Y[:, np.newaxis])

    assert_greater(f1_score(Y, np.hstack(svm_class_weight.predict(X_graphs))),
                   f1_score(Y, np.hstack(svm.predict(X_graphs))))
Пример #3
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def test_standard_svm_blobs_2d_class_weight():
    # no edges, reduce to crammer-singer svm
    X, Y = make_blobs(n_samples=210,
                      centers=3,
                      random_state=1,
                      cluster_std=3,
                      shuffle=False)
    X = np.hstack([X, np.ones((X.shape[0], 1))])
    X, Y = X[:170], Y[:170]

    X_graphs = [(x[np.newaxis, :], np.empty((0, 2), dtype=np.int)) for x in X]

    pbl = GraphCRF(n_features=3, n_states=3, inference_method='unary')
    svm = OneSlackSSVM(pbl, check_constraints=False, C=1000)

    svm.fit(X_graphs, Y[:, np.newaxis])

    weights = 1. / np.bincount(Y)
    weights *= len(weights) / np.sum(weights)

    pbl_class_weight = GraphCRF(n_features=3,
                                n_states=3,
                                class_weight=weights,
                                inference_method='unary')
    svm_class_weight = OneSlackSSVM(pbl_class_weight,
                                    C=10,
                                    check_constraints=False,
                                    break_on_bad=False)
    svm_class_weight.fit(X_graphs, Y[:, np.newaxis])

    assert_greater(f1_score(Y, np.hstack(svm_class_weight.predict(X_graphs))),
                   f1_score(Y, np.hstack(svm.predict(X_graphs))))
Пример #4
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def test_constraint_removal():
    digits = load_digits()
    X, y = digits.data, digits.target
    y = 2 * (y % 2) - 1  # even vs odd as +1 vs -1
    X = X / 16.
    pbl = BinarySVMModel(n_features=X.shape[1])
    clf_no_removal = OneSlackSSVM(model=pbl, max_iter=500, verbose=1, C=10,
                                  inactive_window=0, tol=0.01)
    clf_no_removal.fit(X, y)
    clf = OneSlackSSVM(model=pbl, max_iter=500, verbose=1, C=10, tol=0.01,
                       inactive_threshold=1e-8)
    clf.fit(X, y)

    # results are mostly equal
    # if we decrease tol, they will get more similar
    assert_less(np.mean(clf.predict(X) != clf_no_removal.predict(X)), 0.02)

    # without removal, have as many constraints as iterations
    # +1 for true y constraint
    assert_equal(len(clf_no_removal.objective_curve_) + 1,
                 len(clf_no_removal.constraints_))

    # with removal, there are less constraints than iterations
    assert_less(len(clf.constraints_),
                len(clf.objective_curve_))
Пример #5
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def main():
    print("Please be patient. Will take 5-20 minutes.")
    snakes = load_snakes()
    X_train, Y_train = snakes['X_train'], snakes['Y_train']

    X_train = [one_hot_colors(x) for x in X_train]
    Y_train_flat = [y_.ravel() for y_ in Y_train]

    X_train_directions, X_train_edge_features = prepare_data(X_train)

    # first, train on X with directions only:
    crf = EdgeFeatureGraphCRF(inference_method='qpbo')
    ssvm = OneSlackSSVM(crf, inference_cache=50, C=.1, tol=.1, switch_to='ad3',
                        n_jobs=-1)
    ssvm.fit(X_train_directions, Y_train_flat)

    # Evaluate using confusion matrix.
    # Clearly the middel of the snake is the hardest part.
    X_test, Y_test = snakes['X_test'], snakes['Y_test']
    X_test = [one_hot_colors(x) for x in X_test]
    Y_test_flat = [y_.ravel() for y_ in Y_test]
    X_test_directions, X_test_edge_features = prepare_data(X_test)
    Y_pred = ssvm.predict(X_test_directions)
    print("Results using only directional features for edges")
    print("Test accuracy: %.3f"
          % accuracy_score(np.hstack(Y_test_flat), np.hstack(Y_pred)))
    print(confusion_matrix(np.hstack(Y_test_flat), np.hstack(Y_pred)))

    # now, use more informative edge features:
    crf = EdgeFeatureGraphCRF(inference_method='qpbo')
    ssvm = OneSlackSSVM(crf, inference_cache=50, C=.1, tol=.1, switch_to='ad3',
                        n_jobs=-1)
    ssvm.fit(X_train_edge_features, Y_train_flat)
    Y_pred2 = ssvm.predict(X_test_edge_features)
    print("Results using also input features for edges")
    print("Test accuracy: %.3f"
          % accuracy_score(np.hstack(Y_test_flat), np.hstack(Y_pred2)))
    print(confusion_matrix(np.hstack(Y_test_flat), np.hstack(Y_pred2)))

    # plot stuff
    fig, axes = plt.subplots(2, 2)
    axes[0, 0].imshow(snakes['X_test'][0], interpolation='nearest')
    axes[0, 0].set_title('Input')
    y = Y_test[0].astype(np.int)
    bg = 2 * (y != 0)  # enhance contrast
    axes[0, 1].matshow(y + bg, cmap=plt.cm.Greys)
    axes[0, 1].set_title("Ground Truth")
    axes[1, 0].matshow(Y_pred[0].reshape(y.shape) + bg, cmap=plt.cm.Greys)
    axes[1, 0].set_title("Prediction w/o edge features")
    axes[1, 1].matshow(Y_pred2[0].reshape(y.shape) + bg, cmap=plt.cm.Greys)
    axes[1, 1].set_title("Prediction with edge features")
    for a in axes.ravel():
        a.set_xticks(())
        a.set_yticks(())
    plt.show()
    from IPython.core.debugger import Tracer
    Tracer()()
Пример #6
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def test_one_slack_constraint_caching():
    # testing cutting plane ssvm on easy multinomial dataset
    X, Y = generate_blocks_multinomial(n_samples=10, noise=0.5, seed=0,
                                       size_x=9)
    n_labels = len(np.unique(Y))
    exact_inference = get_installed([('ad3', {'branch_and_bound': True}), "lp"])[0]
    crf = GridCRF(n_states=n_labels, inference_method=exact_inference)
    clf = OneSlackSSVM(model=crf, max_iter=150, C=1,
                       check_constraints=True, break_on_bad=True,
                       inference_cache=50, inactive_window=0)
    clf.fit(X, Y)
    Y_pred = clf.predict(X)
    assert_array_equal(Y, Y_pred)
    assert_equal(len(clf.inference_cache_), len(X))
    # there should be 13 constraints, which are less than the 94 iterations
    # that are done
    # check that we didn't change the behavior of how we construct the cache
    constraints_per_sample = [len(cache) for cache in clf.inference_cache_]
    if exact_inference == "lp":
        assert_equal(len(clf.inference_cache_[0]), 18)
        assert_equal(np.max(constraints_per_sample), 18)
        assert_equal(np.min(constraints_per_sample), 18)
    else:
        assert_equal(len(clf.inference_cache_[0]), 13)
        assert_equal(np.max(constraints_per_sample), 20)
        assert_equal(np.min(constraints_per_sample), 11)
Пример #7
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def test_one_slack_constraint_caching():
    #testing cutting plane ssvm on easy multinomial dataset
    X, Y = generate_blocks_multinomial(n_samples=10,
                                       noise=0.5,
                                       seed=0,
                                       size_x=9)
    n_labels = len(np.unique(Y))
    crf = GridCRF(n_states=n_labels, inference_method='lp')
    clf = OneSlackSSVM(model=crf,
                       max_iter=150,
                       C=1,
                       check_constraints=True,
                       break_on_bad=True,
                       inference_cache=50,
                       inactive_window=0,
                       verbose=10)
    clf.fit(X, Y)
    Y_pred = clf.predict(X)
    assert_array_equal(Y, Y_pred)
    assert_equal(len(clf.inference_cache_), len(X))
    # there should be 11 constraints, which are less than the 94 iterations
    # that are done
    assert_equal(len(clf.inference_cache_[0]), 11)
    # check that we didn't change the behavior of how we construct the cache
    constraints_per_sample = [len(cache) for cache in clf.inference_cache_]
    assert_equal(np.max(constraints_per_sample), 19)
    assert_equal(np.min(constraints_per_sample), 11)
Пример #8
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def msrc():
    models_basedir = 'models/msrc/'
    crf = EdgeCRF(n_states=24, n_features=2028, n_edge_features=4,
                  inference_method='gco')
    clf = OneSlackSSVM(crf, max_iter=10000, C=0.01, verbose=2,
                       tol=0.1, n_jobs=4,
                       inference_cache=100)

    X, Y = load_msrc('train')
    Y = remove_areas(Y)

    start = time()
    clf.fit(X, Y)
    stop = time()

    np.savetxt(models_basedir + 'msrc_full.csv', clf.w)
    with open(models_basedir + 'msrc_full' + '.pickle', 'w') as f:
        cPickle.dump(clf, f)

    X, Y = load_msrc('test')
    Y = remove_areas(Y)

    Y_pred = clf.predict(X)

    print 'Error on test set: %f' % compute_error(Y, Y_pred)
    print 'Score on test set: %f' % clf.score(X, Y)
    print 'Norm of weight vector: |w|=%f' % np.linalg.norm(clf.w)
    print 'Elapsed time: %f s' % (stop - start)

    return clf
Пример #9
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def syntetic_test():
    # test model on different train set size & on different train sets
    results = np.zeros((18, 5))
    full_labeled = np.array([2, 4, 10, 25, 100])
    train_size = 400

    for dataset in xrange(1, 19):
        X, Y = load_syntetic(dataset)

        for j, nfull in enumerate(full_labeled):
            crf = EdgeCRF(n_states=10, n_features=10, n_edge_features=2,
                          inference_method='qpbo')
            clf = OneSlackSSVM(crf, max_iter=10000, C=0.01, verbose=0,
                               tol=0.1, n_jobs=4, inference_cache=100)

            x_train = X[:nfull]
            y_train = Y[:nfull]
            x_test = X[(train_size + 1):]
            y_test = Y[(train_size + 1):]

            try:
                clf.fit(x_train, y_train)
                y_pred = clf.predict(x_test)

                results[dataset - 1, j] = compute_error(y_test, y_pred)

                print 'dataset=%d, nfull=%d, error=%f' % (dataset, nfull,
                                                          results[dataset - 1, j])
            except ValueError:
                print 'dataset=%d, nfull=%d: Failed' % (dataset, nfull)

    np.savetxt('results/syntetic/full_labeled.txt', results)
Пример #10
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def test_binary_blocks_one_slack_graph():
    #testing cutting plane ssvm on easy binary dataset
    # generate graphs explicitly for each example
    X, Y = generate_blocks(n_samples=3)
    crf = GraphCRF(inference_method=inference_method)
    clf = OneSlackSSVM(model=crf, max_iter=100, C=1,
                       check_constraints=True, break_on_bad=True,
                       n_jobs=1, tol=.1)
    x1, x2, x3 = X
    y1, y2, y3 = Y
    n_states = len(np.unique(Y))
    # delete some rows to make it more fun
    x1, y1 = x1[:, :-1], y1[:, :-1]
    x2, y2 = x2[:-1], y2[:-1]
    # generate graphs
    X_ = [x1, x2, x3]
    G = [make_grid_edges(x) for x in X_]

    # reshape / flatten x and y
    X_ = [x.reshape(-1, n_states) for x in X_]
    Y = [y.ravel() for y in [y1, y2, y3]]

    X = list(zip(X_, G))

    clf.fit(X, Y)
    Y_pred = clf.predict(X)
    for y, y_pred in zip(Y, Y_pred):
        assert_array_equal(y, y_pred)
Пример #11
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def msrc():
    models_basedir = 'models/msrc/'
    crf = EdgeCRF(n_states=24, n_features=2028, n_edge_features=4,
                  inference_method='gco')
    clf = OneSlackSSVM(crf, max_iter=10000, C=0.01, verbose=2,
                       tol=0.1, n_jobs=4,
                       inference_cache=100)

    X, Y = load_msrc('train')
    Y = remove_areas(Y)

    start = time()
    clf.fit(X, Y)
    stop = time()

    np.savetxt(models_basedir + 'msrc_full.csv', clf.w)
    with open(models_basedir + 'msrc_full' + '.pickle', 'w') as f:
        pickle.dump(clf, f)

    X, Y = load_msrc('test')
    Y = remove_areas(Y)

    Y_pred = clf.predict(X)

    print('Error on test set: %f' % compute_error(Y, Y_pred))
    print('Score on test set: %f' % clf.score(X, Y))
    print('Norm of weight vector: |w|=%f' % np.linalg.norm(clf.w))
    print('Elapsed time: %f s' % (stop - start))

    return clf
Пример #12
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def test_one_slack_constraint_caching():
    # testing cutting plane ssvm on easy multinomial dataset
    X, Y = generate_blocks_multinomial(n_samples=10, noise=0.5, seed=0,
                                       size_x=9)
    n_labels = len(np.unique(Y))
    exact_inference = get_installed([('ad3', {'branch_and_bound': True}), "lp"])[0]
    crf = GridCRF(n_states=n_labels, inference_method=exact_inference)
    clf = OneSlackSSVM(model=crf, max_iter=150, C=1,
                       check_constraints=True, break_on_bad=True,
                       inference_cache=50, inactive_window=0)
    clf.fit(X, Y)
    Y_pred = clf.predict(X)
    assert_array_equal(Y, Y_pred)
    assert_equal(len(clf.inference_cache_), len(X))
    # there should be 13 constraints, which are less than the 94 iterations
    # that are done
    # check that we didn't change the behavior of how we construct the cache
    constraints_per_sample = [len(cache) for cache in clf.inference_cache_]
    if exact_inference == "lp":
        assert_equal(len(clf.inference_cache_[0]), 18)
        assert_equal(np.max(constraints_per_sample), 18)
        assert_equal(np.min(constraints_per_sample), 18)
    else:
        assert_equal(len(clf.inference_cache_[0]), 13)
        assert_equal(np.max(constraints_per_sample), 20)
        assert_equal(np.min(constraints_per_sample), 11)
Пример #13
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def test_binary_blocks_one_slack_graph():
    #testing cutting plane ssvm on easy binary dataset
    # generate graphs explicitly for each example
    for inference_method in ["dai", "lp"]:
        print("testing %s" % inference_method)
        X, Y = toy.generate_blocks(n_samples=3)
        crf = GraphCRF(inference_method=inference_method)
        clf = OneSlackSSVM(problem=crf, max_iter=100, C=100, verbose=100,
                           check_constraints=True, break_on_bad=True,
                           n_jobs=1)
        x1, x2, x3 = X
        y1, y2, y3 = Y
        n_states = len(np.unique(Y))
        # delete some rows to make it more fun
        x1, y1 = x1[:, :-1], y1[:, :-1]
        x2, y2 = x2[:-1], y2[:-1]
        # generate graphs
        X_ = [x1, x2, x3]
        G = [make_grid_edges(x) for x in X_]

        # reshape / flatten x and y
        X_ = [x.reshape(-1, n_states) for x in X_]
        Y = [y.ravel() for y in [y1, y2, y3]]

        X = zip(X_, G)

        clf.fit(X, Y)
        Y_pred = clf.predict(X)
        for y, y_pred in zip(Y, Y_pred):
            assert_array_equal(y, y_pred)
def train(x_train, y_train, x_test, y_test):
    x_train = np.asarray(x_train, dtype=np.float)
    y_train = np.asarray(y_train, dtype=np.int64)
    # x_test = np.asarray(x_test, dtype=np.float)
    # y_test = np.asarray(y_test, dtype=np.int64)
    x_test = x_train
    y_test = y_train

    from pystruct.learners import NSlackSSVM, OneSlackSSVM, SubgradientSSVM, LatentSSVM, SubgradientLatentSSVM, PrimalDSStructuredSVM
    from pystruct.models import MultiLabelClf, MultiClassClf

    clf = OneSlackSSVM(MultiLabelClf(),
                       C=1,
                       show_loss_every=1,
                       verbose=1,
                       max_iter=1000)
    # print(x_train, y_train)
    # input()
    clf.fit(x_train, y_train)
    result = clf.predict(x_test)
    print('Result: \n', result)
    print('True label:\n', y_test)
    clf.score(x_test, y_test)
    print('\n')

    count = 0
    for i in range(len(result)):
        # print(np.sum(np.square(y_test[i]-result[i])))
        if np.sum(np.square(y_test[i] - result[i])) != 0:
            print('True label: ', y_test[i], 'Predict:  ', result[i])
            count += 1
    print(count)

    translate_vector(x_test, y_test)
Пример #15
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def syntetic():
    # train model on a single set
    models_basedir = 'models/syntetic/'
    crf = EdgeCRF(n_states=10, n_features=10, n_edge_features=2,
                  inference_method='gco')
    clf = OneSlackSSVM(crf, max_iter=10000, C=0.01, verbose=2,
                       tol=0.1, n_jobs=4, inference_cache=100)

    X, Y = load_syntetic(1)

    x_train, x_test, y_train, y_test = train_test_split(X, Y,
                                                        train_size=100,
                                                        random_state=179)

    start = time()
    clf.fit(x_train, y_train)
    stop = time()

    np.savetxt(models_basedir + 'syntetic_full.csv', clf.w)
    with open(models_basedir + 'syntetic_full' + '.pickle', 'w') as f:
        cPickle.dump(clf, f)

    y_pred = clf.predict(x_test)

    print 'Error on test set: %f' % compute_error(y_test, y_pred)
    print 'Score on test set: %f' % clf.score(x_test, y_test)
    print 'Score on train set: %f' % clf.score(x_train, y_train)
    print 'Norm of weight vector: |w|=%f' % np.linalg.norm(clf.w)
    print 'Elapsed time: %f s' % (stop - start)

    return clf
Пример #16
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def syntetic_test():
    # test model on different train set size & on different train sets
    results = np.zeros((18, 5))
    full_labeled = np.array([2, 4, 10, 25, 100])
    train_size = 400

    for dataset in range(1, 19):
        X, Y = load_syntetic(dataset)

        for j, nfull in enumerate(full_labeled):
            crf = EdgeCRF(n_states=10, n_features=10, n_edge_features=2,
                          inference_method='qpbo')
            clf = OneSlackSSVM(crf, max_iter=10000, C=0.01, verbose=0,
                               tol=0.1, n_jobs=4, inference_cache=100)

            x_train = X[:nfull]
            y_train = Y[:nfull]
            x_test = X[(train_size + 1):]
            y_test = Y[(train_size + 1):]

            try:
                clf.fit(x_train, y_train)
                y_pred = clf.predict(x_test)

                results[dataset - 1, j] = compute_error(y_test, y_pred)

                print('dataset=%d, nfull=%d, error=%f' % (dataset, nfull,
                                                          results[dataset - 1, j]))
            except ValueError:
                print('dataset=%d, nfull=%d: Failed' % (dataset, nfull))

    np.savetxt('results/syntetic/full_labeled.txt', results)
Пример #17
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def CRF_pred(eeg1,
             eeg2,
             emg,
             y,
             eeg1test,
             eeg2test,
             emgtest,
             C=0.9,
             weight_shift=0,
             max_iter=1000,
             fs=128):

    # For the ith iteration, select as trainin the sub_indices other than those at index i for train_index
    eeg1_train = eeg1.values
    eeg2_train = eeg2.values
    emg_train = emg.values
    y_train = y.values

    # The test subject is the one at index i
    eeg1_test = eeg1test.values
    eeg2_test = eeg2test.values
    emg_test = emgtest.values

    # CRF Model Preprocessing
    eeg1_ = process_EEG(eeg1_train)
    eeg2_ = process_EEG(eeg2_train)
    emg_ = process_EMG(emg_train)
    xtrain_ = np.concatenate((eeg1_, eeg2_, emg_), axis=1)
    ytrain_classes = np.reshape(y_train, (y_train.shape[0], ))
    ytrain_ = y_train

    eeg1_ = process_EEG(eeg1_test)
    eeg2_ = process_EEG(eeg2_test)
    emg_ = process_EMG(emg_test)
    xtest_ = np.concatenate((eeg1_, eeg2_, emg_), axis=1)

    xtrain_crf = np.reshape(
        xtrain_,
        (3, -1, xtrain_.shape[1]))  # Reshape so that it works with CRF
    ytrain_crf = np.reshape(ytrain_,
                            (3, -1)) - 1  # Reshape so that it works with CRF

    # CRF Model fitting:
    classes = np.unique(ytrain_)
    weights_crf = compute_class_weight("balanced", list(classes),
                                       list(ytrain_classes))
    weights_crf[0] = weights_crf[0] + (2.5 * weight_shift)
    weights_crf[1] = weights_crf[1] + (1.5 * weight_shift)

    model = ChainCRF(class_weight=weights_crf)
    ssvm = OneSlackSSVM(model=model, C=C, max_iter=max_iter)
    ssvm.fit(xtrain_crf, ytrain_crf)

    # Test on the third guy
    xtest_crf = np.reshape(xtest_, (2, -1, xtest_.shape[1]))
    y_pred_crf = ssvm.predict(xtest_crf)
    y_pred_crf = np.asarray(y_pred_crf).reshape(-1) + 1
    return y_pred_crf
Пример #18
0
def losocv_CRF_prepro(xtrain, y, C=0.5, weight_shift=0, max_iter=1000, fs=128):
    """Leave one subject out cross validation for the CRF model becasuse it requires
    special datahandling. Input should be a Pandas Dataframe."""

    epochs = 21600
    num_sub = 3
    # Indices of the subjects
    sub_indices = [
        np.arange(0, epochs),
        np.arange(epochs, epochs * 2),
        np.arange(epochs * 2, epochs * 3)
    ]
    res = []

    for i in range(len(sub_indices)):

        # For the ith iteration, select as trainin the sub_indices other than those at index i for train_index
        train_index = np.concatenate(
            [sub_indices[(i + 1) % num_sub], sub_indices[(i + 2) % num_sub]])
        xtrain_ = xtrain[train_index]
        y_train = y.values[train_index]
        ytrain_ = y_train

        # The test subject is the one at index i
        test_index = sub_indices[i]
        xtest_ = xtrain[test_index]
        y_test = y.values[test_index]
        ytest_ = y_test

        # CRF Model Preprocessing
        ytrain_classes = np.reshape(y_train, (y_train.shape[0], ))
        xtrain_crf = np.reshape(
            xtrain_,
            (2, -1, xtrain_.shape[1]))  # Reshape so that it works with CRF
        ytrain_crf = np.reshape(
            ytrain_, (2, -1)) - 1  # Reshape so that it works with CRF

        # CRF Model fitting:
        classes = np.unique(ytrain_)
        weights_crf = compute_class_weight("balanced", list(classes),
                                           list(ytrain_classes))
        weights_crf[0] = weights_crf[0] + (2.5 * weight_shift)
        weights_crf[1] = weights_crf[1] + (1.5 * weight_shift)

        model = ChainCRF(class_weight=weights_crf)
        ssvm = OneSlackSSVM(model=model, C=C, max_iter=max_iter)
        ssvm.fit(xtrain_crf, ytrain_crf)

        # Test on the third guy
        xtest_crf = np.reshape(xtest_, (1, -1, xtest_.shape[1]))
        ytest_crf = np.reshape(ytest_, (1, -1)) - 1
        y_pred_crf = ssvm.predict(xtest_crf)
        y_pred_crf = np.asarray(y_pred_crf).reshape(-1) + 1

        resy = sklearn.metrics.balanced_accuracy_score(ytest_, y_pred_crf)
        print("Iteration, result:", i, resy)
        res.append(resy)
    return res
Пример #19
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def test(nfiles):
    X = []
    Y = []
    X_tst = []
    Y_tst = []
    ntrain = nfiles
    ntest = 5*nfiles
    print("Training/testing with %d/%d files." % (ntrain,ntest))
    start = time.clock()   
 
    filename = '../maps/MAPS_AkPnCGdD_2/AkPnCGdD/MUS'
    #filename = '../maps/MAPS_AkPnCGdD_1/AkPnCGdD/ISOL/NO'
    files = dirs.get_files_with_extension(filename, '.mid')
    train_files = files[:ntrain]
    print("\t" + str(train_files))
    #test_files = files[ntrain:ntest+ntrain]
    # for legit testing
    test_files = files[-ntest:]
    map(per_file, train_files,
      it.repeat(X, ntrain), it.repeat(Y, ntrain))
    map(per_file, test_files,
      it.repeat(X_tst, ntest), it.repeat(Y_tst, ntest))

    end = time.clock()
    print("\tRead time: %f" % (end - start))
    print("\tnWindows train: " + str([X[i].shape[0] for i in range(len(X))]))
    start = time.clock()   

    crf = ChainCRF(n_states=2)
    clf = OneSlackSSVM(model=crf, C=100, n_jobs=-1,
          inference_cache=100, tol=.1)
    clf.fit(np.array(X), np.array(Y))

    end = time.clock()
    print("\tTrain time: %f" % (end - start))
    start = time.clock()   

    Y_pred = clf.predict(X_tst)
    comp = []
    for i in range(len(Y_tst)):
      for j in range(len(Y_tst[i])):
        comp.append((Y_tst[i][j], Y_pred[i][j]))
        print Y_tst[i][j],
      print
      for j in range(len(Y_tst[i])):
        print Y_pred[i][j],
      print
      print

    print("\tTrue positives: %d" % comp.count((1,1)))
    print("\tTrue negatives: %d" % comp.count((0,0)))
    print("\tFalse positives: %d" % comp.count((0,1)))
    print("\tFalse negatives: %d" % comp.count((1,0)))
    

    end = time.clock()
    print("\tTest time: %f" % (end - start))
Пример #20
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def model_test(k, head, tail):
    """
    CRF训练和预测
    """
    each_fold_time = time.time()  #开始计时

    #divide train set and test set
    train_id = dataId[head:tail]
    test_id = dataId[:head] + dataId[tail:]

    X_train = X_arr[train_id, :]
    Y_train = Y_arr[train_id]
    X_test = X_arr[test_id, :]
    Y_test = Y_arr[test_id]
    campTest = Camp_arr[test_id]
    #ends divide train set and test set
    if len(X_train) > 0:
        #实例化CRF
        EFGCRF = EdgeFeatureGraphCRF(inference_method='qpbo',
                                     class_weight=CLASS_WEIGHT)
        if LEARNER == "OneSlackSSVM":
            #利用OneSlackSSVM训练模型参数
            ssvm = OneSlackSSVM(EFGCRF,
                                C=.1,
                                tol=.1,
                                max_iter=100,
                                switch_to='ad3')
        elif LEARNER == "FrankWolfeSSVM":
            #利用FrankWolfeSSVM训练模型参数
            ssvm = FrankWolfeSSVM(EFGCRF, C=.1, tol=.1, max_iter=100)
        else:
            #没有选择分类器退出
            pass

        ssvm.fit(X_train, Y_train)
        Y_pred = ssvm.predict(X_test)

        df_result = statistic_result(Y_pred, Y_test, campTest)
        V_precision = precision_score(df_result["label"], df_result["pred"])
        V_recall = recall_score(df_result["label"], df_result["pred"])
        V_f1 = f1_score(df_result["label"], df_result["pred"])

        camps_pred, camps_lbl = statistic_campaign_result(Y_pred, Y_test)
        C_precision = precision_score(camps_lbl, camps_pred)
        C_recall = recall_score(camps_lbl, camps_pred)
        C_f1 = f1_score(camps_lbl, camps_pred)

        result_Queue.put(
            [V_precision, V_recall, V_f1, C_precision, C_recall, C_f1])

    else:
        print("TRAIN SET is NULL")

    print("the {}th fold using time: {:.4f} min".format(
        k + 1, (time.time() - each_fold_time) / 60))
    del X_train, Y_train, X_test, Y_test, Y_pred, campTest
Пример #21
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def test_multinomial_blocks_one_slack():
    #testing cutting plane ssvm on easy multinomial dataset
    X, Y = generate_blocks_multinomial(n_samples=10, noise=0.5, seed=0)
    n_labels = len(np.unique(Y))
    crf = GridCRF(n_states=n_labels, inference_method=inference_method)
    clf = OneSlackSSVM(model=crf, max_iter=150, C=1,
                       check_constraints=True, break_on_bad=True, tol=.1,
                       inference_cache=50)
    clf.fit(X, Y)
    Y_pred = clf.predict(X)
    assert_array_equal(Y, Y_pred)
Пример #22
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def test_one_slack_attractive_potentials():
    # test that submodular SSVM can learn the block dataset
    X, Y = generate_blocks(n_samples=10)
    crf = GridCRF(inference_method=inference_method)
    submodular_clf = OneSlackSSVM(
        model=crf, max_iter=200, C=1, check_constraints=True, negativity_constraint=[5], inference_cache=50
    )
    submodular_clf.fit(X, Y)
    Y_pred = submodular_clf.predict(X)
    assert_array_equal(Y, Y_pred)
    assert_true(submodular_clf.w[5] < 0)
def test_equal_class_weights():
    # test that equal class weight is the same as no class weight
    X, Y = make_blobs(n_samples=80, centers=3, random_state=42)
    X = np.hstack([X, np.ones((X.shape[0], 1))])
    X_train, X_test, Y_train, Y_test = X[:40], X[40:], Y[:40], Y[40:]

    pbl = MultiClassClf(n_features=3, n_classes=3)
    svm = OneSlackSSVM(pbl, C=10)

    svm.fit(X_train, Y_train)
    predict_no_class_weight = svm.predict(X_test)

    pbl_class_weight = MultiClassClf(n_features=3, n_classes=3,
                                     class_weight=np.ones(3))
    svm_class_weight = OneSlackSSVM(pbl_class_weight, C=10)
    svm_class_weight.fit(X_train, Y_train)
    predict_class_weight = svm_class_weight.predict(X_test)

    assert_array_equal(predict_no_class_weight, predict_class_weight)
    assert_array_almost_equal(svm.w, svm_class_weight.w)
def test_class_weights():
    X, Y = make_blobs(n_samples=210, centers=3, random_state=1, cluster_std=3,
                      shuffle=False)
    X = np.hstack([X, np.ones((X.shape[0], 1))])
    X, Y = X[:170], Y[:170]

    pbl = MultiClassClf(n_features=3, n_classes=3)
    svm = OneSlackSSVM(pbl, C=10)

    svm.fit(X, Y)

    weights = 1. / np.bincount(Y)
    weights *= len(weights) / np.sum(weights)
    pbl_class_weight = MultiClassClf(n_features=3, n_classes=3,
                                     class_weight=weights)
    svm_class_weight = OneSlackSSVM(pbl_class_weight, C=10)
    svm_class_weight.fit(X, Y)

    assert_greater(f1_score(Y, svm_class_weight.predict(X)),
                   f1_score(Y, svm.predict(X)))
Пример #25
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def test_one_slack_attractive_potentials():
    # test that submodular SSVM can learn the block dataset
    X, Y = toy.generate_blocks(n_samples=10)
    crf = GridCRF()
    submodular_clf = OneSlackSSVM(model=crf, max_iter=200, C=100, verbose=1,
                                  check_constraints=True,
                                  positive_constraint=[5], n_jobs=-1)
    submodular_clf.fit(X, Y)
    Y_pred = submodular_clf.predict(X)
    assert_array_equal(Y, Y_pred)
    assert_true(submodular_clf.w[5] < 0)  # don't ask me about signs
Пример #26
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def test_multinomial_blocks_one_slack():
    #testing cutting plane ssvm on easy multinomial dataset
    X, Y = generate_blocks_multinomial(n_samples=10, noise=0.5, seed=0)
    n_labels = len(np.unique(Y))
    crf = GridCRF(n_states=n_labels, inference_method=inference_method)
    clf = OneSlackSSVM(model=crf, max_iter=150, C=1,
                       check_constraints=True, break_on_bad=True, tol=.1,
                       inference_cache=50)
    clf.fit(X, Y)
    Y_pred = clf.predict(X)
    assert_array_equal(Y, Y_pred)
Пример #27
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def test_class_weights():
    # test that equal class weight is the same as no class weight
    X, Y = make_blobs(n_samples=210, centers=3, random_state=1, cluster_std=3,
                      shuffle=False)
    X = np.hstack([X, np.ones((X.shape[0], 1))])
    X, Y = X[:170], Y[:170]

    pbl = CrammerSingerSVMModel(n_features=3, n_classes=3)
    svm = OneSlackSSVM(pbl, verbose=10, C=10)

    svm.fit(X, Y)

    weights = 1. / np.bincount(Y)
    weights *= len(weights) / np.sum(weights)
    pbl_class_weight = CrammerSingerSVMModel(n_features=3, n_classes=3,
                                             class_weight=weights)
    svm_class_weight = OneSlackSSVM(pbl_class_weight, verbose=10, C=10)
    svm_class_weight.fit(X, Y)

    assert_greater(f1_score(Y, svm_class_weight.predict(X)),
                   f1_score(Y, svm.predict(X)))
Пример #28
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def test_one_slack_repellent_potentials():
    # test non-submodular problem with and without submodularity constraint
    # dataset is checkerboard
    X, Y = generate_checker()
    crf = GridCRF(inference_method=inference_method)
    clf = OneSlackSSVM(model=crf, max_iter=10, C=0.01, check_constraints=True)
    clf.fit(X, Y)
    Y_pred = clf.predict(X)
    # standard crf can predict perfectly
    assert_array_equal(Y, Y_pred)

    submodular_clf = OneSlackSSVM(
        model=crf, max_iter=10, C=0.01, check_constraints=True, negativity_constraint=[4, 5, 6]
    )
    submodular_clf.fit(X, Y)
    Y_pred = submodular_clf.predict(X)
    assert_less(submodular_clf.score(X, Y), 0.99)
    # submodular crf can not do better than unaries
    for i, x in enumerate(X):
        y_pred_unaries = crf.inference(x, np.array([1, 0, 0, 1, 0, 0, 0]))
        assert_array_equal(y_pred_unaries, Y_pred[i])
Пример #29
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def test_equal_class_weights():
    # test that equal class weight is the same as no class weight
    X, Y = make_blobs(n_samples=80, centers=3, random_state=42)
    X = np.hstack([X, np.ones((X.shape[0], 1))])
    X_train, X_test, Y_train, Y_test = X[:40], X[40:], Y[:40], Y[40:]

    pbl = MultiClassClf(n_features=3, n_classes=3)
    svm = OneSlackSSVM(pbl, C=10)

    svm.fit(X_train, Y_train)
    predict_no_class_weight = svm.predict(X_test)

    pbl_class_weight = MultiClassClf(n_features=3,
                                     n_classes=3,
                                     class_weight=np.ones(3))
    svm_class_weight = OneSlackSSVM(pbl_class_weight, C=10)
    svm_class_weight.fit(X_train, Y_train)
    predict_class_weight = svm_class_weight.predict(X_test)

    assert_array_equal(predict_no_class_weight, predict_class_weight)
    assert_array_almost_equal(svm.w, svm_class_weight.w)
Пример #30
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def test_one_slack_attractive_potentials():
    # test that submodular SSVM can learn the block dataset
    X, Y = generate_blocks(n_samples=10)
    crf = GridCRF(inference_method=inference_method)
    submodular_clf = OneSlackSSVM(model=crf, max_iter=200, C=1,
                                  check_constraints=True,
                                  negativity_constraint=[5],
                                  inference_cache=50)
    submodular_clf.fit(X, Y)
    Y_pred = submodular_clf.predict(X)
    assert_array_equal(Y, Y_pred)
    assert_true(submodular_clf.w[5] < 0)
Пример #31
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def test_multinomial_blocks_one_slack():
    #testing cutting plane ssvm on easy multinomial dataset
    X, Y = toy.generate_blocks_multinomial(n_samples=10, noise=0.3,
                                           seed=0)
    n_labels = len(np.unique(Y))
    for inference_method in ['lp']:
        crf = GridCRF(n_states=n_labels, inference_method=inference_method)
        clf = OneSlackSSVM(problem=crf, max_iter=50, C=100, verbose=100,
                           check_constraints=True, break_on_bad=True)
        clf.fit(X, Y)
        Y_pred = clf.predict(X)
        assert_array_equal(Y, Y_pred)
Пример #32
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def test_blobs_2d_one_slack():
    # make two gaussian blobs
    X, Y = make_blobs(n_samples=80, centers=3, random_state=42)
    # we have to add a constant 1 feature by hand :-/
    X = np.hstack([X, np.ones((X.shape[0], 1))])

    X_train, X_test, Y_train, Y_test = X[:40], X[40:], Y[:40], Y[40:]

    pbl = MultiClassClf(n_features=3, n_classes=3)
    svm = OneSlackSSVM(pbl, check_constraints=True, C=1000)

    svm.fit(X_train, Y_train)
    assert_array_equal(Y_test, np.hstack(svm.predict(X_test)))
Пример #33
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def test_one_slack_repellent_potentials():
    # test non-submodular problem with and without submodularity constraint
    # dataset is checkerboard
    X, Y = generate_checker()
    crf = GridCRF(inference_method=inference_method)
    clf = OneSlackSSVM(model=crf, max_iter=10, C=.01,
                       check_constraints=True)
    clf.fit(X, Y)
    Y_pred = clf.predict(X)
    # standard crf can predict perfectly
    assert_array_equal(Y, Y_pred)

    submodular_clf = OneSlackSSVM(model=crf, max_iter=10, C=.01,
                                  check_constraints=True,
                                  negativity_constraint=[4, 5, 6])
    submodular_clf.fit(X, Y)
    Y_pred = submodular_clf.predict(X)
    assert_less(submodular_clf.score(X, Y), .99)
    # submodular crf can not do better than unaries
    for i, x in enumerate(X):
        y_pred_unaries = crf.inference(x, np.array([1, 0, 0, 1, 0, 0, 0]))
        assert_array_equal(y_pred_unaries, Y_pred[i])
Пример #34
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def test_blobs_2d_one_slack():
    # make two gaussian blobs
    X, Y = make_blobs(n_samples=80, centers=2, random_state=1)
    Y = 2 * Y - 1
    # we have to add a constant 1 feature by hand :-/
    X = np.hstack([X, np.ones((X.shape[0], 1))])
    X_train, X_test, Y_train, Y_test = X[:40], X[40:], Y[:40], Y[40:]

    pbl = BinarySVMModel(n_features=3)
    svm = OneSlackSSVM(pbl, verbose=30, C=1000)

    svm.fit(X_train, Y_train)
    assert_array_equal(Y_test, np.hstack(svm.predict(X_test)))
Пример #35
0
def test_one_slack_repellent_potentials():
    # test non-submodular learning with and without positivity constraint
    # dataset is checkerboard
    X, Y = toy.generate_checker()
    for inference_method in ["lp", "qpbo", "ad3"]:
        crf = GridCRF(inference_method=inference_method)
        clf = OneSlackSSVM(model=crf, max_iter=10, C=100, verbose=0,
                           check_constraints=True, n_jobs=-1)
        clf.fit(X, Y)
        Y_pred = clf.predict(X)
        # standard crf can predict perfectly
        assert_array_equal(Y, Y_pred)

        submodular_clf = OneSlackSSVM(model=crf, max_iter=10, C=100,
                                      verbose=0, check_constraints=True,
                                      positive_constraint=[4, 5, 6], n_jobs=-1)
        submodular_clf.fit(X, Y)
        Y_pred = submodular_clf.predict(X)
        # submodular crf can not do better than unaries
        for i, x in enumerate(X):
            y_pred_unaries = crf.inference(x, np.array([1, 0, 0, 1, 0, 0, 0]))
            assert_array_equal(y_pred_unaries, Y_pred[i])
def test_blobs_2d_one_slack():
    # make two gaussian blobs
    X, Y = make_blobs(n_samples=80, centers=3, random_state=42)
    # we have to add a constant 1 feature by hand :-/
    X = np.hstack([X, np.ones((X.shape[0], 1))])

    X_train, X_test, Y_train, Y_test = X[:40], X[40:], Y[:40], Y[40:]

    pbl = MultiClassClf(n_features=3, n_classes=3)
    svm = OneSlackSSVM(pbl, check_constraints=True, C=1000)

    svm.fit(X_train, Y_train)
    assert_array_equal(Y_test, np.hstack(svm.predict(X_test)))
Пример #37
0
def test_class_weights():
    X, Y = make_blobs(n_samples=210,
                      centers=3,
                      random_state=1,
                      cluster_std=3,
                      shuffle=False)
    X = np.hstack([X, np.ones((X.shape[0], 1))])
    X, Y = X[:170], Y[:170]

    pbl = MultiClassClf(n_features=3, n_classes=3)
    svm = OneSlackSSVM(pbl, C=10)

    svm.fit(X, Y)

    weights = 1. / np.bincount(Y)
    weights *= len(weights) / np.sum(weights)
    pbl_class_weight = MultiClassClf(n_features=3,
                                     n_classes=3,
                                     class_weight=weights)
    svm_class_weight = OneSlackSSVM(pbl_class_weight, C=10)
    svm_class_weight.fit(X, Y)

    assert_greater(f1_score(Y, svm_class_weight.predict(X), average='macro'),
                   f1_score(Y, svm.predict(X), average='macro'))
Пример #38
0
    def fit_crf(self):
        for C in self.C_range:
            print("Testing C value: {}".format(C))
            model = EdgeFeatureGraphCRF(inference_method="ad3")
            ssvm = OneSlackSSVM(model,
                                inference_cache=50,
                                C=C,
                                tol=self.tol,
                                max_iter=self.max_iter,
                                n_jobs=4,
                                verbose=False)
            ssvm.fit(self.X_train, self.y_train)
            predictions = [x for x in ssvm.predict(self.X_dev)]
            self.evaluate_predictions(predictions, self.y_dev)

        # Fit against the whole dataset except test
        # Is this approach correct?
        model = EdgeFeatureGraphCRF(inference_method="ad3")
        ssvm = OneSlackSSVM(model,
                            inference_cache=50,
                            C=0.03,
                            tol=self.tol,
                            max_iter=self.max_iter,
                            n_jobs=4,
                            verbose=False)
        X_train_dev = np.concatenate([self.X_train, self.X_dev])
        y_train_dev = np.concatenate([self.y_train, self.y_dev])
        ssvm.fit(X_train_dev, y_train_dev)

        if self.eval_against_test:
            predictions = [x for x in ssvm.predict(self.X_test)]
            print("Test set evaluation")
            self.evaluate_predictions(predictions, self.y_test)

        self.model = ssvm
        return ssvm
Пример #39
0
def test_standard_svm_blobs_2d():
    # no edges, reduce to crammer-singer svm
    X, Y = make_blobs(n_samples=80, centers=3, random_state=42)
    # we have to add a constant 1 feature by hand :-/
    X = np.hstack([X, np.ones((X.shape[0], 1))])

    X_train, X_test, Y_train, Y_test = X[:40], X[40:], Y[:40], Y[40:]
    X_train_graphs = [(x[np.newaxis, :], np.empty((0, 2), dtype=np.int)) for x in X_train]

    X_test_graphs = [(x[np.newaxis, :], np.empty((0, 2), dtype=np.int)) for x in X_test]

    pbl = GraphCRF(n_features=3, n_states=3)
    svm = OneSlackSSVM(pbl, verbose=10, check_constraints=True, C=1000)

    svm.fit(X_train_graphs, Y_train[:, np.newaxis])
    assert_array_equal(Y_test, np.hstack(svm.predict(X_test_graphs)))
Пример #40
0
def msrc_test():
    # test model on different train set sizes
    basedir = '../data/msrc/trainmasks/'
    models_basedir = 'models/msrc/'
    quality = []

    Xtest, Ytest = load_msrc('test')
    Ytest = remove_areas(Ytest)
    Xtrain, Ytrain = load_msrc('train')
    Ytrain = remove_areas(Ytrain)

    for n_train in [20, 40, 80, 160, 276]:
        crf = EdgeCRF(n_states=24, n_features=2028, n_edge_features=4,
                      inference_method='gco')
        clf = OneSlackSSVM(crf, max_iter=1000, C=0.01, verbose=0,
                           tol=0.1, n_jobs=4, inference_cache=100)

        if n_train != 276:
            train_mask = np.genfromtxt(basedir + 'trainMaskX%d.txt' % n_train)
            train_mask = train_mask[:277].astype(np.bool)
        else:
            train_mask = np.ones(276).astype(np.bool)

        curX = []
        curY = []
        for (s, x, y) in zip(train_mask, Xtrain, Ytrain):
            if s:
                curX.append(x)
                curY.append(y)

        start = time()
        clf.fit(curX, curY)
        stop = time()

        np.savetxt(models_basedir + 'test_model_%d.csv' % n_train, clf.w)
        with open(models_basedir + 'test_model_%d' % n_train + '.pickle', 'w') as f:
            pickle.dump(clf, f)

        Ypred = clf.predict(Xtest)

        q = 1 - compute_error(Ytest, Ypred)

        print('n_train=%d, quality=%f, time=%f' % (n_train, q, stop - start))
        quality.append(q)

    np.savetxt('results/msrc/msrc_full.txt', quality)
Пример #41
0
def msrc_test():
    # test model on different train set sizes
    basedir = '../data/msrc/trainmasks/'
    models_basedir = 'models/msrc/'
    quality = []

    Xtest, Ytest = load_msrc('test')
    Ytest = remove_areas(Ytest)
    Xtrain, Ytrain = load_msrc('train')
    Ytrain = remove_areas(Ytrain)

    for n_train in [20, 40, 80, 160, 276]:
        crf = EdgeCRF(n_states=24, n_features=2028, n_edge_features=4,
                      inference_method='gco')
        clf = OneSlackSSVM(crf, max_iter=1000, C=0.01, verbose=0,
                           tol=0.1, n_jobs=4, inference_cache=100)

        if n_train != 276:
            train_mask = np.genfromtxt(basedir + 'trainMaskX%d.txt' % n_train)
            train_mask = train_mask[:277].astype(np.bool)
        else:
            train_mask = np.ones(276).astype(np.bool)

        curX = []
        curY = []
        for (s, x, y) in zip(train_mask, Xtrain, Ytrain):
            if s:
                curX.append(x)
                curY.append(y)

        start = time()
        clf.fit(curX, curY)
        stop = time()

        np.savetxt(models_basedir + 'test_model_%d.csv' % n_train, clf.w)
        with open(models_basedir + 'test_model_%d' % n_train + '.pickle', 'w') as f:
            cPickle.dump(clf, f)

        Ypred = clf.predict(Xtest)

        q = 1 - compute_error(Ytest, Ypred)

        print 'n_train=%d, quality=%f, time=%f' % (n_train, q, stop - start)
        quality.append(q)

    np.savetxt('results/msrc/msrc_full.txt', quality)
Пример #42
0
def conditional_random_fields(X, y):
	"""
	"""

	X_ = [(np.atleast_2d(x), np.empty((0, 2), dtype=np.int)) for x in X]
	Y = y.reshape(-1, 1)

	X_train, X_test, y_train, y_test = train_test_split(X_, Y)

	pbl = GraphCRF()
	svm = OneSlackSSVM(pbl)

	svm.fit(X_train, y_train)
	y_pred = np.vstack(svm.predict(X_test))
	print("Score with pystruct crf svm: %f "
	      % (np.mean(y_pred == y_test)))
	print classification_report(y_test, y_pred)
	plot_confusion_matrix(y_test, y_pred)
class PystructSequenceLearner(SequenceLearner):
    def __init__(self):
        # the model
        self.model = ChainCRF(directed=True)
        # the learner
        self.learner = OneSlackSSVM(model=self.model,
                                    C=.1,
                                    inference_cache=50,
                                    tol=0.1,
                                    n_jobs=1)
        # self.learner = StructuredPerceptron(model=self.model, average=True)

    def fit(self, X, y):
        # Train linear chain CRF
        self.learner.fit(X, y)

    def predict(self, X):
        return self.learner.predict(X)
Пример #44
0
def test_standard_svm_blobs_2d():
    # no edges, reduce to crammer-singer svm
    X, Y = make_blobs(n_samples=80, centers=3, random_state=42)
    # we have to add a constant 1 feature by hand :-/
    X = np.hstack([X, np.ones((X.shape[0], 1))])

    X_train, X_test, Y_train, Y_test = X[:40], X[40:], Y[:40], Y[40:]
    X_train_graphs = [(x[np.newaxis, :], np.empty((0, 2), dtype=np.int))
                      for x in X_train]

    X_test_graphs = [(x[np.newaxis, :], np.empty((0, 2), dtype=np.int))
                     for x in X_test]

    pbl = GraphCRF(n_features=3, n_states=3, inference_method='unary')
    svm = OneSlackSSVM(pbl, check_constraints=True, C=1000)

    svm.fit(X_train_graphs, Y_train[:, np.newaxis])
    assert_array_equal(Y_test, np.hstack(svm.predict(X_test_graphs)))
Пример #45
0
def test_one_slack_constraint_caching():
    #testing cutting plane ssvm on easy multinomial dataset
    X, Y = toy.generate_blocks_multinomial(n_samples=10, noise=0.5,
                                           seed=0, size_x=9)
    n_labels = len(np.unique(Y))
    crf = GridCRF(n_states=n_labels)
    clf = OneSlackSSVM(model=crf, max_iter=150, C=1,
                       check_constraints=True, break_on_bad=True,
                       inference_cache=50, inactive_window=0)
    clf.fit(X, Y)
    Y_pred = clf.predict(X)
    assert_array_equal(Y, Y_pred)
    assert_equal(len(clf.inference_cache_), len(X))
    # there should be 21 constraints, which are less than the 94 iterations
    # that are done
    assert_equal(len(clf.inference_cache_[0]), 21)
    # check that we didn't change the behavior of how we construct the cache
    constraints_per_sample = [len(cache) for cache in clf.inference_cache_]
    assert_equal(np.max(constraints_per_sample), 21)
    assert_equal(np.min(constraints_per_sample), 21)
Пример #46
0
def test_one_slack_constraint_caching():
    #testing cutting plane ssvm on easy multinomial dataset
    X, Y = toy.generate_blocks_multinomial(n_samples=10, noise=0.3,
                                           seed=0)
    n_labels = len(np.unique(Y))
    crf = GridCRF(n_states=n_labels, inference_method='lp')
    clf = OneSlackSSVM(problem=crf, max_iter=50, C=100, verbose=100,
                       check_constraints=True, break_on_bad=True,
                       inference_cache=50)
    clf.fit(X, Y)
    Y_pred = clf.predict(X)
    assert_array_equal(Y, Y_pred)
    assert_equal(len(clf.inference_cache_), len(X))
    # there should be 9 constraints, which are less than the 16 iterations
    # that are done
    assert_equal(len(clf.inference_cache_[0]), 9)
    # check that we didn't change the behavior of how we construct the cache
    constraints_per_sample = [len(cache) for cache in clf.inference_cache_]
    assert_equal(np.max(constraints_per_sample), 10)
    assert_equal(np.min(constraints_per_sample), 8)
Пример #47
0
def CRF_pred_prepro(xtrain,
                    y,
                    xtest,
                    C=0.9,
                    weight_shift=0,
                    max_iter=1000,
                    fs=128):

    y_train = y.values

    # CRF Model Preprocessing
    xtrain_ = xtrain
    ytrain_classes = np.reshape(y_train, (y_train.shape[0], ))
    ytrain_ = y_train
    xtest_ = xtest
    xtrain_crf = np.reshape(
        xtrain_,
        (3, -1, xtrain_.shape[1]))  # Reshape so that it works with CRF
    ytrain_crf = np.reshape(ytrain_,
                            (3, -1)) - 1  # Reshape so that it works with CRF

    # CRF Model fitting:
    classes = np.unique(ytrain_)
    weights_crf = compute_class_weight("balanced", list(classes),
                                       list(ytrain_classes))
    weights_crf[0] = weights_crf[0] + (2.5 * weight_shift)
    weights_crf[1] = weights_crf[1] + (1.5 * weight_shift)

    model = ChainCRF(class_weight=weights_crf)
    ssvm = OneSlackSSVM(model=model, C=C, max_iter=max_iter)
    ssvm.fit(xtrain_crf, ytrain_crf)

    # Test on the third guy
    xtest_crf = np.reshape(xtest_, (2, -1, xtest_.shape[1]))
    y_pred_crf = ssvm.predict(xtest_crf)
    y_pred_crf = np.asarray(y_pred_crf).reshape(-1) + 1
    return y_pred_crf
Пример #48
0
fw_bc_svm = FrankWolfeSSVM(model, C=.1, max_iter=50)
fw_batch_svm = FrankWolfeSSVM(model, C=.1, max_iter=50, batch_mode=True)

# n-slack cutting plane ssvm
start = time()
n_slack_svm.fit(X_train_bias, y_train)
time_n_slack_svm = time() - start
y_pred = np.hstack(n_slack_svm.predict(X_test_bias))
print("Score with pystruct n-slack ssvm: %f (took %f seconds)"
      % (np.mean(y_pred == y_test), time_n_slack_svm))

## 1-slack cutting plane ssvm
start = time()
one_slack_svm.fit(X_train_bias, y_train)
time_one_slack_svm = time() - start
y_pred = np.hstack(one_slack_svm.predict(X_test_bias))
print("Score with pystruct 1-slack ssvm: %f (took %f seconds)"
      % (np.mean(y_pred == y_test), time_one_slack_svm))

#online subgradient ssvm
start = time()
subgradient_svm.fit(X_train_bias, y_train)
time_subgradient_svm = time() - start
y_pred = np.hstack(subgradient_svm.predict(X_test_bias))

print("Score with pystruct subgradient ssvm: %f (took %f seconds)"
      % (np.mean(y_pred == y_test), time_subgradient_svm))

# the standard one-vs-rest multi-class would probably be as good and faster
# but solving a different model
libsvm = LinearSVC(multi_class='crammer_singer', C=.1)
        ## string labels to label ids
        label2id = {l:i for i,l in enumerate(set(y_train_flat))}
        id2label = {l:i for i,l in label2id.items()}
        y_train = [np.array([label2id[tok[2]] for tok in sentence]) 
                for sentence in iob_train]

        if args.oneslack:
            ### fit oneslack ssvm
            crf = ChainCRF()
            os_ssvm = OneSlackSSVM(crf, verbose=args.verbose, n_jobs=-1,
                    use_memmapping_pool=0, 
                    show_loss_every=20,
                    tol=0.01, cache_tol=0.1)
            os_ssvm.fit(list(X_train_tsvd), y_train)
            test_os_ssvm_preds = [[id2label[i] for i in sent] 
                    for sent in os_ssvm.predict(X_test_tsvd)]
            test_conll_os_ssvm = conlleval_fmt(iob_test, test_os_ssvm_preds)
            test_conll_os_ssvm_file = open('test_conll_os_ssvm.txt', 'wb')
            for sentence in test_conll_os_ssvm:
                test_conll_os_ssvm_file.write(bytes(sentence, 'UTF-8'))
            test_conll_os_ssvm_file.close()
            print(conlleval_results('test_conll_os_ssvm.txt'))

        if args.subgrad:
            ### fit subgradient ssvm                                                       
            crf = ChainCRF()                                                            
            sg_ssvm = SubgradientSSVM(crf, max_iter=200, 
                    verbose=args.verbose, n_jobs=-1,                           
                    use_memmapping_pool=0, show_loss_every=20, shuffle=True)                                            
            sg_ssvm.fit(list(X_train_tsvd), y_train)                                    
            test_sg_ssvm_preds = [[id2label[i] for i in sent]                           
Пример #50
0
def main():
    print("Please be patient. Will take 5-20 minutes.")
    snakes = load_snakes()
    X_train, Y_train = snakes['X_train'], snakes['Y_train']

    X_train = [one_hot_colors(x) for x in X_train]
    Y_train_flat = [y_.ravel() for y_ in Y_train]

    X_train_directions, X_train_edge_features = prepare_data(X_train)

    if 'ogm' in get_installed():
        inference = ('ogm', {'alg': 'fm'})
    else:
        inference = 'qpbo'
    # first, train on X with directions only:
    crf = EdgeFeatureGraphCRF(inference_method=inference)
    ssvm = OneSlackSSVM(crf,
                        inference_cache=50,
                        C=.1,
                        tol=.1,
                        max_iter=100,
                        n_jobs=1)
    ssvm.fit(X_train_directions, Y_train_flat)

    # Evaluate using confusion matrix.
    # Clearly the middel of the snake is the hardest part.
    X_test, Y_test = snakes['X_test'], snakes['Y_test']
    X_test = [one_hot_colors(x) for x in X_test]
    Y_test_flat = [y_.ravel() for y_ in Y_test]
    X_test_directions, X_test_edge_features = prepare_data(X_test)
    Y_pred = ssvm.predict(X_test_directions)
    print("Results using only directional features for edges")
    print("Test accuracy: %.3f" %
          accuracy_score(np.hstack(Y_test_flat), np.hstack(Y_pred)))
    print(confusion_matrix(np.hstack(Y_test_flat), np.hstack(Y_pred)))

    # now, use more informative edge features:
    crf = EdgeFeatureGraphCRF(inference_method=inference)
    ssvm = OneSlackSSVM(crf,
                        inference_cache=50,
                        C=.1,
                        tol=.1,
                        switch_to='ad3',
                        n_jobs=1)
    ssvm.fit(X_train_edge_features, Y_train_flat)
    Y_pred2 = ssvm.predict(X_test_edge_features)
    print("Results using also input features for edges")
    print("Test accuracy: %.3f" %
          accuracy_score(np.hstack(Y_test_flat), np.hstack(Y_pred2)))
    print(confusion_matrix(np.hstack(Y_test_flat), np.hstack(Y_pred2)))

    # plot stuff
    fig, axes = plt.subplots(2, 2)
    axes[0, 0].imshow(snakes['X_test'][0], interpolation='nearest')
    axes[0, 0].set_title('Input')
    y = Y_test[0].astype(np.int)
    bg = 2 * (y != 0)  # enhance contrast
    axes[0, 1].matshow(y + bg, cmap=plt.cm.Greys)
    axes[0, 1].set_title("Ground Truth")
    axes[1, 0].matshow(Y_pred[0].reshape(y.shape) + bg, cmap=plt.cm.Greys)
    axes[1, 0].set_title("Prediction w/o edge features")
    axes[1, 1].matshow(Y_pred2[0].reshape(y.shape) + bg, cmap=plt.cm.Greys)
    axes[1, 1].set_title("Prediction with edge features")
    for a in axes.ravel():
        a.set_xticks(())
        a.set_yticks(())
    plt.show()
    from IPython.core.debugger import Tracer
    Tracer()()
Пример #51
0
    inference = ('ogm', {'alg': 'fm'})
else:
    inference = 'qpbo'
# first, train on X with directions only:
crf = EdgeFeatureGraphCRF(inference_method=inference)
ssvm = OneSlackSSVM(crf, inference_cache=50, C=.1, tol=.1, max_iter=100,
                    n_jobs=1)
ssvm.fit(X_train_directions, Y_train_flat)

# Evaluate using confusion matrix.
# Clearly the middel of the snake is the hardest part.
X_test, Y_test = snakes['X_test'], snakes['Y_test']
X_test = [one_hot_colors(x) for x in X_test]
Y_test_flat = [y_.ravel() for y_ in Y_test]
X_test_directions, X_test_edge_features = prepare_data(X_test)
Y_pred = ssvm.predict(X_test_directions)
print("Results using only directional features for edges")
print("Test accuracy: %.3f"
      % accuracy_score(np.hstack(Y_test_flat), np.hstack(Y_pred)))
print(confusion_matrix(np.hstack(Y_test_flat), np.hstack(Y_pred)))

# now, use more informative edge features:
crf = EdgeFeatureGraphCRF(inference_method=inference)
ssvm = OneSlackSSVM(crf, inference_cache=50, C=.1, tol=.1, switch_to='ad3',
                    n_jobs=1)
ssvm.fit(X_train_edge_features, Y_train_flat)
Y_pred2 = ssvm.predict(X_test_edge_features)
print("Results using also input features for edges")
print("Test accuracy: %.3f"
      % accuracy_score(np.hstack(Y_test_flat), np.hstack(Y_pred2)))
print(confusion_matrix(np.hstack(Y_test_flat), np.hstack(Y_pred2)))
Пример #52
0
    yeast = fetch_mldata("yeast")

    X = yeast.data
    X = np.hstack([X, np.ones((X.shape[0], 1))])
    y = yeast.target.toarray().astype(np.int).T

    X_train, X_test = X[:1500], X[1500:]
    y_train, y_test = y[:1500], y[1500:]

else:
    scene = load_scene()
    X_train, X_test = scene['X_train'], scene['X_test']
    y_train, y_test = scene['y_train'], scene['y_test']

n_labels = y_train.shape[1]
full = np.vstack([x for x in itertools.combinations(range(n_labels), 2)])
tree = chow_liu_tree(y_train)

#tree_model = MultiLabelClf(edges=tree, inference_method=('ogm', {'alg': 'dyn'}))
tree_model = MultiLabelClf(edges=tree, inference_method='max-product')

tree_ssvm = OneSlackSSVM(tree_model, inference_cache=50, C=.1, tol=0.01)

print("fitting tree model...")
tree_ssvm.fit(X_train, y_train)

print("Training loss tree model: %f"
      % hamming_loss(y_train, np.vstack(tree_ssvm.predict(X_train))))
print("Test loss tree model: %f"
      % hamming_loss(y_test, np.vstack(tree_ssvm.predict(X_test))))
Пример #53
0
    for num in new_index_list:
        new_array = Xtest_scaler[num[0]:num[1], :]
        Xtest_scale.append(new_array)
    Xtest_scale = np.array(Xtest_scale)
    print Xtest_scale.shape
    print 'Test set scaled'
    ssvm.fit(Xtrain_scale, y_train)
    print 'Model fit'

    # Storing model weights for plot of transition probabilities
    if type(transition_states) == str:
        transition_states = ssvm.w[-49:].reshape(7, 7)
    else:
        transition_states = transition_states + ssvm.w[-49:].reshape(7, 7)

    predicted = ssvm.predict(Xtest_scale)
    print 'Predictions made'
    # Metrics
    fold_cm = confusion_matrix(np.hstack(y_test), np.hstack(predicted))
    if type(total_confusion_matrix) == str:
        total_confusion_matrix = fold_cm
    else:
        total_confusion_matrix = total_confusion_matrix + fold_cm

    report = classification_report(np.hstack(y_test), np.hstack(predicted))
    for line in report.split('\n'):
        print line
    print 'Metrics written'

# Code for plotting matrix depicting transition probabilities
# for the CRF model averaged across 10 folds of CV.
Пример #54
0
class SSVM:
    """Structured SVM wrapper"""
    def __init__(self,
                 inference_train,
                 inference_pred,
                 dat_obj,
                 C=1.0,
                 share_params=True,
                 multi_label=True,
                 poi_info=None,
                 debug=False):
        assert (C > 0)
        self.C = C
        self.inference_train = inference_train
        self.inference_pred = inference_pred
        self.share_params = share_params
        self.multi_label = multi_label
        self.dat_obj = dat_obj
        self.debug = debug
        self.trained = False

        if poi_info is None:
            self.poi_info = None
        else:
            self.poi_info = poi_info

        self.scaler_node = MinMaxScaler(feature_range=(-1, 1), copy=False)
        self.scaler_edge = MinMaxScaler(feature_range=(-1, 1), copy=False)

    def train(self, trajid_list, n_jobs=4):
        if self.poi_info is None:
            self.poi_info = self.dat_obj.calc_poi_info(trajid_list)

        # build POI_ID <--> POI__INDEX mapping for POIs used to train CRF
        # which means only POIs in traj such that len(traj) >= 2 are included
        poi_set = {
            p
            for tid in trajid_list for p in self.dat_obj.traj_dict[tid]
            if len(self.dat_obj.traj_dict[tid]) >= 2
        }
        self.poi_list = sorted(poi_set)
        self.poi_id_dict, self.poi_id_rdict = dict(), dict()
        for idx, poi in enumerate(self.poi_list):
            self.poi_id_dict[poi] = idx
            self.poi_id_rdict[idx] = poi

        # generate training data
        train_traj_list = [
            self.dat_obj.traj_dict[k] for k in trajid_list
            if len(self.dat_obj.traj_dict[k]) >= 2
        ]
        node_features_list = Parallel(n_jobs=n_jobs)(
            delayed(calc_node_features)(tr[0], len(tr), self.poi_list,
                                        self.poi_info, self.dat_obj)
            for tr in train_traj_list)
        edge_features = calc_edge_features(trajid_list, self.poi_list,
                                           self.poi_info, self.dat_obj)

        # feature scaling: node features
        # should each example be flattened to one vector before scaling?
        self.fdim_node = node_features_list[0].shape
        X_node_all = np.vstack(node_features_list)
        X_node_all = self.scaler_node.fit_transform(X_node_all)
        X_node_all = X_node_all.reshape(-1, self.fdim_node[0],
                                        self.fdim_node[1])

        # feature scaling: edge features
        fdim_edge = edge_features.shape
        edge_features = self.scaler_edge.fit_transform(
            edge_features.reshape(fdim_edge[0] * fdim_edge[1], -1))
        self.edge_features = edge_features.reshape(fdim_edge)

        assert (len(train_traj_list) == X_node_all.shape[0])
        X_train = [(X_node_all[k, :, :], self.edge_features.copy(),
                    (self.poi_id_dict[train_traj_list[k][0]],
                     len(train_traj_list[k])))
                   for k in range(len(train_traj_list))]
        y_train = [
            np.array([self.poi_id_dict[k] for k in tr])
            for tr in train_traj_list
        ]
        assert (len(X_train) == len(y_train))

        # train
        sm = MyModel(inference_train=self.inference_train,
                     inference_pred=self.inference_pred,
                     share_params=self.share_params,
                     multi_label=self.multi_label)
        if self.debug is True:
            print('C:', self.C)
        verbose = 1 if self.debug is True else 0
        self.osssvm = OneSlackSSVM(model=sm,
                                   C=self.C,
                                   n_jobs=n_jobs,
                                   verbose=verbose)
        try:
            self.osssvm.fit(X_train, y_train, initialize=True)
            self.trained = True
            print('SSVM training finished.')
        # except ValueError:
        except:
            self.trained = False
            sys.stderr.write('SSVM training FAILED.\n')
            # raise
        return self.trained

    def predict(self, startPOI, nPOI):
        assert (self.trained is True)
        if startPOI not in self.poi_list:
            return None
        X_node_test = calc_node_features(startPOI, nPOI, self.poi_list,
                                         self.poi_info, self.dat_obj)

        # feature scaling
        # should each example be flattened to one vector before scaling?
        # X_node_test = X_node_test.reshape(1, -1) # flatten test example to a vector
        X_node_test = self.scaler_node.transform(X_node_test)
        # X_node_test = X_node_test.reshape(self.fdim)

        X_test = [(X_node_test, self.edge_features,
                   (self.poi_id_dict[startPOI], nPOI))]
        y_hat_list = self.osssvm.predict(X_test)[0]
        # print(y_hat_list)

        return [
            np.array([self.poi_id_rdict[x] for x in y_hat])
            for y_hat in y_hat_list
        ]
Пример #55
0
crf = EdgeFeatureGraphCRF(inference_method=inference)
ssvm = OneSlackSSVM(crf,
                    inference_cache=50,
                    C=.1,
                    tol=.1,
                    max_iter=100,
                    n_jobs=1)
ssvm.fit(X_train_directions, Y_train_flat)

# Evaluate using confusion matrix.
# Clearly the middel of the snake is the hardest part.
X_test, Y_test = snakes['X_test'], snakes['Y_test']
X_test = [one_hot_colors(x) for x in X_test]
Y_test_flat = [y_.ravel() for y_ in Y_test]
X_test_directions, X_test_edge_features = prepare_data(X_test)
Y_pred = ssvm.predict(X_test_directions)
print("Results using only directional features for edges")
print("Test accuracy: %.3f" %
      accuracy_score(np.hstack(Y_test_flat), np.hstack(Y_pred)))
print(confusion_matrix(np.hstack(Y_test_flat), np.hstack(Y_pred)))

# now, use more informative edge features:
crf = EdgeFeatureGraphCRF(inference_method=inference)
ssvm = OneSlackSSVM(crf,
                    inference_cache=50,
                    C=.1,
                    tol=.1,
                    switch_to='ad3',
                    n_jobs=1)
ssvm.fit(X_train_edge_features, Y_train_flat)
Y_pred2 = ssvm.predict(X_test_edge_features)
Пример #56
0
#inference = 'qpbo'
#I'm interested in AD3 inference.
inference = 'ad3'

# first, train on X with directions only:
crf = EdgeFeatureGraphCRF(inference_method=inference)
ssvm = OneSlackSSVM(crf, inference_cache=50, C=.1, tol=.1, max_iter=100,
                    n_jobs=1)
t0 = time.time()
ssvm.fit(X_train_directions, Y_train_flat)
print("Model EdgeFeatureGraphCRF fitted. %.1fs"%(time.time()-t0))

Y_GT = np.hstack(Y_test_flat)
print("- Results using only directional features for edges. %.1fs"%(time.time()-t0))
t0 = time.time()
Y_pred = ssvm.predict(X_test_directions)
REPORT(Y_GT, Y_pred, time.time()-t0)

print "- Result with binarized graph"
t0 = time.time()
Y_pred = ssvm.predict(X_test_directions, [True]*len(X_test_directions))
REPORT(Y_GT, Y_pred, time.time()-t0)


#Predict under constraints
def buildConstraints(X, bOne=True):
    """
    We iterate over each graph, and make sure that for each, we constrain to have a single instances of classes 1 to 9
    (or atmost one) 
    
    The constraints must be a list of tuples like ( <operator>, <unaries>, <states>, <negated> )
Пример #57
0
print("val end export")
Xtrain = np.loadtxt(vfnumpypath + "Xtrain.txt")
Ytrain = np.loadtxt(vfnumpypath + "Ytrain.txt", dtype="int")
print("train end export")

#independent Model
independent_model = MultiLabelClf(inference_method='unary')
independent_ssvm = OneSlackSSVM(independent_model, C=.1, tol=0.01)

print("fitting independent model...")
independent_ssvm.fit(Xtrain, Ytrain)

#print np.vstack(independent_ssvm.predict(Xval))[1,:]

print("Test exact matching ratio: %f" % check_exactmatchratio(
    Yval, np.vstack(independent_ssvm.predict(Xval)), datatotest))

print(
    f1_score(Yval[3, :],
             np.vstack(independent_ssvm.predict(Xtrain))[3, :],
             average='macro'))
'''
print("Training loss independent model: %f"
      % hamming_loss(Ytrain, np.vstack(independent_ssvm.predict(Xtrain))))
print("Test loss independent model: %f"
      % hamming_loss(Yval, np.vstack(independent_ssvm.predict(Xval))))
print Yval.shape
print Yval[1,:]
      
'''
Пример #58
0
print("Training SSVM")
inference = 'qpbo'
# first, train on X with directions only:
crf = EdgeFeatureGraphCRF(inference_method=inference)
ssvm = OneSlackSSVM(crf,
                    inference_cache=50,
                    C=1.,
                    tol=.1,
                    max_iter=500,
                    n_jobs=4)

Y_flat = [y_.ravel() for y_ in Y]
Y_flat = np.asarray(
    [Y_flat[i][j] for i in range(len(Y_flat)) for j in range(len(Y_flat[i]))])
ssvm.fit(X, Y)
Z_bin = ssvm.predict(X)
Z_flat = np.asarray(
    [Z_bin[i][j] for i in range(len(Z_bin)) for j in range(len(Z_bin[i]))])
f1_score = metrics.f1_score(Y_flat, Z_flat, average='weighted')
conf_mat = metrics.confusion_matrix(Y_flat, Z_flat)
TPR = conf_mat[0][0] / (conf_mat[0][0] + conf_mat[0][1])
FPR = conf_mat[1][0] / (conf_mat[1][0] + conf_mat[1][1])
print('Results with classifier: ' + ssvm.__class__.__name__)
print('TPR/FPR = ' + str(TPR) + '/' + str(FPR))
print('F1-score = ' + str(f1_score))

my_classifier = ssvm
# Run prediction on the img_idx-th image
img_idx = 0
the_img = imgs[img_idx]
the_gt = gt_imgs[img_idx]