def main():
    # load MNIST images
    images, labels = dataset.load_train_images()

    # config
    config = aae.config

    # settings
    # _l -> labeled
    # _u -> unlabeled
    max_epoch = 1000
    num_trains_per_epoch = 5000
    batchsize_l = 100
    batchsize_u = 100
    alpha = 1

    # seed
    np.random.seed(args.seed)
    if args.gpu_device != -1:
        cuda.cupy.random.seed(args.seed)

    # save validation accuracy per epoch
    csv_results = []

    # create semi-supervised split
    num_validation_data = 10000
    num_labeled_data = 100
    num_types_of_label = 10
    training_images_l, training_labels_l, training_images_u, validation_images, validation_labels = dataset.create_semisupervised(
        images,
        labels,
        num_validation_data,
        num_labeled_data,
        num_types_of_label,
        seed=args.seed)
    print training_labels_l

    # classification
    # 0 -> true sample
    # 1 -> generated sample
    class_true = aae.to_variable(np.zeros(batchsize_u, dtype=np.int32))
    class_fake = aae.to_variable(np.ones(batchsize_u, dtype=np.int32))

    # training
    progress = Progress()
    for epoch in xrange(1, max_epoch):
        progress.start_epoch(epoch, max_epoch)
        sum_loss_reconstruction = 0
        sum_loss_supervised = 0
        sum_loss_discriminator = 0
        sum_loss_generator = 0

        for t in xrange(num_trains_per_epoch):
            # sample from data distribution
            images_l, label_onehot_l, label_ids_l = dataset.sample_labeled_data(
                training_images_l, training_labels_l, batchsize_l,
                config.ndim_x, config.ndim_y)
            images_u = dataset.sample_unlabeled_data(training_images_u,
                                                     batchsize_u,
                                                     config.ndim_x)

            # reconstruction phase
            q_y_x_u, z_u = aae.encode_x_yz(images_u, apply_softmax=True)
            reconstruction_u = aae.decode_yz_x(q_y_x_u, z_u)
            loss_reconstruction = F.mean_squared_error(
                aae.to_variable(images_u), reconstruction_u)
            aae.backprop_generator(loss_reconstruction)
            aae.backprop_decoder(loss_reconstruction)

            # adversarial phase
            y_fake_u, z_fake_u = aae.encode_x_yz(images_u, apply_softmax=True)
            z_true_u = sampler.gaussian(batchsize_u,
                                        config.ndim_z,
                                        mean=0,
                                        var=1)
            y_true_u = sampler.onehot_categorical(batchsize_u, config.ndim_y)
            discrimination_z_true = aae.discriminate_z(z_true_u,
                                                       apply_softmax=False)
            discrimination_y_true = aae.discriminate_y(y_true_u,
                                                       apply_softmax=False)
            discrimination_z_fake = aae.discriminate_z(z_fake_u,
                                                       apply_softmax=False)
            discrimination_y_fake = aae.discriminate_y(y_fake_u,
                                                       apply_softmax=False)
            loss_discriminator_z = F.softmax_cross_entropy(
                discrimination_z_true, class_true) + F.softmax_cross_entropy(
                    discrimination_z_fake, class_fake)
            loss_discriminator_y = F.softmax_cross_entropy(
                discrimination_y_true, class_true) + F.softmax_cross_entropy(
                    discrimination_y_fake, class_fake)
            loss_discriminator = loss_discriminator_z + loss_discriminator_y
            aae.backprop_discriminator(loss_discriminator)

            # adversarial phase
            y_fake_u, z_fake_u = aae.encode_x_yz(images_u, apply_softmax=True)
            discrimination_z_fake = aae.discriminate_z(z_fake_u,
                                                       apply_softmax=False)
            discrimination_y_fake = aae.discriminate_y(y_fake_u,
                                                       apply_softmax=False)
            loss_generator_z = F.softmax_cross_entropy(discrimination_z_fake,
                                                       class_true)
            loss_generator_y = F.softmax_cross_entropy(discrimination_y_fake,
                                                       class_true)
            loss_generator = loss_generator_z + loss_generator_y
            aae.backprop_generator(loss_generator)

            # supervised phase
            unnormalized_q_y_x_l, z_l = aae.encode_x_yz(images_l,
                                                        apply_softmax=False)
            loss_supervised = F.softmax_cross_entropy(
                unnormalized_q_y_x_l, aae.to_variable(label_ids_l))
            aae.backprop_generator(loss_supervised)

            sum_loss_reconstruction += float(loss_reconstruction.data)
            sum_loss_supervised += float(loss_supervised.data)
            sum_loss_discriminator += float(loss_discriminator.data)
            sum_loss_generator += float(loss_generator.data)

            if t % 10 == 0:
                progress.show(t, num_trains_per_epoch, {})

        aae.save(args.model_dir)

        # validation phase
        # split validation data to reduce gpu memory consumption
        images_v, _, label_ids_v = dataset.sample_labeled_data(
            validation_images, validation_labels, num_validation_data,
            config.ndim_x, config.ndim_y)
        images_v_segments = np.split(images_v, num_validation_data // 500)
        label_ids_v_segments = np.split(label_ids_v,
                                        num_validation_data // 500)
        num_correct = 0
        for images_v, labels_v in zip(images_v_segments, label_ids_v_segments):
            predicted_labels = aae.argmax_x_label(images_v, test=True)
            for i, label in enumerate(predicted_labels):
                if label == labels_v[i]:
                    num_correct += 1
        validation_accuracy = num_correct / float(num_validation_data)

        progress.show(
            num_trains_per_epoch, num_trains_per_epoch, {
                "loss_r": sum_loss_reconstruction / num_trains_per_epoch,
                "loss_s": sum_loss_supervised / num_trains_per_epoch,
                "loss_d": sum_loss_discriminator / num_trains_per_epoch,
                "loss_g": sum_loss_generator / num_trains_per_epoch,
                "accuracy": validation_accuracy
            })

        # write accuracy to csv
        csv_results.append([epoch, validation_accuracy])
        data = pd.DataFrame(csv_results)
        data.columns = ["epoch", "accuracy"]
        data.to_csv("{}/result.csv".format(args.model_dir))
Exemple #2
0
	pylab.subplot(num_clusters, num_plots_per_cluster + 2, n * (num_plots_per_cluster + 2) + 1)
	pylab.imshow(head_x[n].reshape((image_width, image_height)), interpolation="none")
	pylab.axis("off")

# plot elements in cluster
counts = [0 for i in xrange(num_clusters)]
indices = np.arange(len(images))
np.random.shuffle(indices)
batchsize = 500

i = 0
x_batch = np.zeros((batchsize, ndim_x), dtype=np.float32)
for n in xrange(len(images) / batchsize):
	for b in xrange(batchsize):
		x_batch[b] = images[indices[i]]
		i += 1
	labels = aae.argmax_x_label(x_batch, test=True)
	for m in xrange(labels.size):
		cluster = int(labels[m])
		counts[cluster] += 1
		if counts[cluster] <= num_plots_per_cluster:
			x = (x_batch[m] + 1.0) / 2.0
			pylab.subplot(num_clusters, num_plots_per_cluster + 2, cluster * (num_plots_per_cluster + 2) + 2 + counts[cluster])
			pylab.imshow(x.reshape((image_width, image_height)), interpolation="none")
			pylab.axis("off")

fig = pylab.gcf()
fig.set_size_inches(num_plots_per_cluster, num_clusters)
pylab.savefig("{}/clusters.png".format(args.plot_dir))