def main()

in train.py [0:0]


def main():
    print("Local rank: ", hvd.local_rank(), hvd.size())

    logdir = osp.join(FLAGS.logdir, FLAGS.exp)
    if hvd.rank() == 0:
        if not osp.exists(logdir):
            os.makedirs(logdir)
        logger = TensorBoardOutputFormat(logdir)
    else:
        logger = None

    LABEL = None
    print("Loading data...")
    if FLAGS.dataset == 'cifar10':
        dataset = Cifar10(augment=FLAGS.augment, rescale=FLAGS.rescale)
        test_dataset = Cifar10(train=False, rescale=FLAGS.rescale)
        channel_num = 3

        X_NOISE = tf.placeholder(shape=(None, 32, 32, 3), dtype=tf.float32)
        X = tf.placeholder(shape=(None, 32, 32, 3), dtype=tf.float32)
        LABEL = tf.placeholder(shape=(None, 10), dtype=tf.float32)
        LABEL_POS = tf.placeholder(shape=(None, 10), dtype=tf.float32)

        if FLAGS.large_model:
            model = ResNet32Large(
                num_channels=channel_num,
                num_filters=128,
                train=True)
        elif FLAGS.larger_model:
            model = ResNet32Larger(
                num_channels=channel_num,
                num_filters=128)
        elif FLAGS.wider_model:
            model = ResNet32Wider(
                num_channels=channel_num,
                num_filters=192)
        else:
            model = ResNet32(
                num_channels=channel_num,
                num_filters=128)

    elif FLAGS.dataset == 'imagenet':
        dataset = Imagenet(train=True)
        test_dataset = Imagenet(train=False)
        channel_num = 3
        X_NOISE = tf.placeholder(shape=(None, 32, 32, 3), dtype=tf.float32)
        X = tf.placeholder(shape=(None, 32, 32, 3), dtype=tf.float32)
        LABEL = tf.placeholder(shape=(None, 1000), dtype=tf.float32)
        LABEL_POS = tf.placeholder(shape=(None, 1000), dtype=tf.float32)

        model = ResNet32Wider(
            num_channels=channel_num,
            num_filters=256)

    elif FLAGS.dataset == 'imagenetfull':
        channel_num = 3
        X_NOISE = tf.placeholder(shape=(None, 128, 128, 3), dtype=tf.float32)
        X = tf.placeholder(shape=(None, 128, 128, 3), dtype=tf.float32)
        LABEL = tf.placeholder(shape=(None, 1000), dtype=tf.float32)
        LABEL_POS = tf.placeholder(shape=(None, 1000), dtype=tf.float32)

        model = ResNet128(
            num_channels=channel_num,
            num_filters=64)

    elif FLAGS.dataset == 'mnist':
        dataset = Mnist(rescale=FLAGS.rescale)
        test_dataset = dataset
        channel_num = 1
        X_NOISE = tf.placeholder(shape=(None, 28, 28), dtype=tf.float32)
        X = tf.placeholder(shape=(None, 28, 28), dtype=tf.float32)
        LABEL = tf.placeholder(shape=(None, 10), dtype=tf.float32)
        LABEL_POS = tf.placeholder(shape=(None, 10), dtype=tf.float32)

        model = MnistNet(
            num_channels=channel_num,
            num_filters=FLAGS.num_filters)

    elif FLAGS.dataset == 'dsprites':
        dataset = DSprites(
            cond_shape=FLAGS.cond_shape,
            cond_size=FLAGS.cond_size,
            cond_pos=FLAGS.cond_pos,
            cond_rot=FLAGS.cond_rot)
        test_dataset = dataset
        channel_num = 1

        X_NOISE = tf.placeholder(shape=(None, 64, 64), dtype=tf.float32)
        X = tf.placeholder(shape=(None, 64, 64), dtype=tf.float32)

        if FLAGS.dpos_only:
            LABEL = tf.placeholder(shape=(None, 2), dtype=tf.float32)
            LABEL_POS = tf.placeholder(shape=(None, 2), dtype=tf.float32)
        elif FLAGS.dsize_only:
            LABEL = tf.placeholder(shape=(None, 1), dtype=tf.float32)
            LABEL_POS = tf.placeholder(shape=(None, 1), dtype=tf.float32)
        elif FLAGS.drot_only:
            LABEL = tf.placeholder(shape=(None, 2), dtype=tf.float32)
            LABEL_POS = tf.placeholder(shape=(None, 2), dtype=tf.float32)
        elif FLAGS.cond_size:
            LABEL = tf.placeholder(shape=(None, 1), dtype=tf.float32)
            LABEL_POS = tf.placeholder(shape=(None, 1), dtype=tf.float32)
        elif FLAGS.cond_shape:
            LABEL = tf.placeholder(shape=(None, 3), dtype=tf.float32)
            LABEL_POS = tf.placeholder(shape=(None, 3), dtype=tf.float32)
        elif FLAGS.cond_pos:
            LABEL = tf.placeholder(shape=(None, 2), dtype=tf.float32)
            LABEL_POS = tf.placeholder(shape=(None, 2), dtype=tf.float32)
        elif FLAGS.cond_rot:
            LABEL = tf.placeholder(shape=(None, 2), dtype=tf.float32)
            LABEL_POS = tf.placeholder(shape=(None, 2), dtype=tf.float32)
        else:
            LABEL = tf.placeholder(shape=(None, 3), dtype=tf.float32)
            LABEL_POS = tf.placeholder(shape=(None, 3), dtype=tf.float32)

        model = DspritesNet(
            num_channels=channel_num,
            num_filters=FLAGS.num_filters,
            cond_size=FLAGS.cond_size,
            cond_shape=FLAGS.cond_shape,
            cond_pos=FLAGS.cond_pos,
            cond_rot=FLAGS.cond_rot)

    print("Done loading...")

    if FLAGS.dataset == "imagenetfull":
        # In the case of full imagenet, use custom_tensorflow dataloader
        data_loader = TFImagenetLoader('train', FLAGS.batch_size, hvd.rank(), hvd.size(), rescale=FLAGS.rescale)
    else:
        data_loader = DataLoader(
            dataset,
            batch_size=FLAGS.batch_size,
            num_workers=FLAGS.data_workers,
            drop_last=True,
            shuffle=True)

    batch_size = FLAGS.batch_size

    weights = [model.construct_weights('context_0')]

    Y = tf.placeholder(shape=(None), dtype=tf.int32)

    # Varibles to run in training
    X_SPLIT = tf.split(X, FLAGS.num_gpus)
    X_NOISE_SPLIT = tf.split(X_NOISE, FLAGS.num_gpus)
    LABEL_SPLIT = tf.split(LABEL, FLAGS.num_gpus)
    LABEL_POS_SPLIT = tf.split(LABEL_POS, FLAGS.num_gpus)
    LABEL_SPLIT_INIT = list(LABEL_SPLIT)
    tower_grads = []
    tower_gen_grads = []
    x_mod_list = []

    optimizer = AdamOptimizer(FLAGS.lr, beta1=0.0, beta2=0.999)
    optimizer = hvd.DistributedOptimizer(optimizer)

    for j in range(FLAGS.num_gpus):

        if FLAGS.model_cclass:
            ind_batch_size = FLAGS.batch_size // FLAGS.num_gpus
            label_tensor = tf.Variable(
                tf.convert_to_tensor(
                    np.reshape(
                        np.tile(np.eye(10), (FLAGS.batch_size, 1, 1)),
                        (FLAGS.batch_size * 10, 10)),
                    dtype=tf.float32),
                trainable=False,
                dtype=tf.float32)
            x_split = tf.tile(
                tf.reshape(
                    X_SPLIT[j], (ind_batch_size, 1, 32, 32, 3)), (1, 10, 1, 1, 1))
            x_split = tf.reshape(x_split, (ind_batch_size * 10, 32, 32, 3))
            energy_pos = model.forward(
                x_split,
                weights[0],
                label=label_tensor,
                stop_at_grad=False)

            energy_pos_full = tf.reshape(energy_pos, (ind_batch_size, 10))
            energy_partition_est = tf.reduce_logsumexp(
                energy_pos_full, axis=1, keepdims=True)
            uniform = tf.random_uniform(tf.shape(energy_pos_full))
            label_tensor = tf.argmax(-energy_pos_full -
                                     tf.log(-tf.log(uniform)) - energy_partition_est, axis=1)
            label = tf.one_hot(label_tensor, 10, dtype=tf.float32)
            label = tf.Print(label, [label_tensor, energy_pos_full])
            LABEL_SPLIT[j] = label
            energy_pos = tf.concat(energy_pos, axis=0)
        else:
            energy_pos = [
                model.forward(
                    X_SPLIT[j],
                    weights[0],
                    label=LABEL_POS_SPLIT[j],
                    stop_at_grad=False)]
            energy_pos = tf.concat(energy_pos, axis=0)

        print("Building graph...")
        x_mod = x_orig = X_NOISE_SPLIT[j]

        x_grads = []

        energy_negs = []
        loss_energys = []

        energy_negs.extend([model.forward(tf.stop_gradient(
            x_mod), weights[0], label=LABEL_SPLIT[j], stop_at_grad=False, reuse=True)])
        eps_begin = tf.zeros(1)

        steps = tf.constant(0)
        c = lambda i, x: tf.less(i, FLAGS.num_steps)

        def langevin_step(counter, x_mod):
            x_mod = x_mod + tf.random_normal(tf.shape(x_mod),
                                             mean=0.0,
                                             stddev=0.005 * FLAGS.rescale * FLAGS.noise_scale)

            energy_noise = energy_start = tf.concat(
                [model.forward(
                        x_mod,
                        weights[0],
                        label=LABEL_SPLIT[j],
                        reuse=True,
                        stop_at_grad=False,
                        stop_batch=True)],
                axis=0)

            x_grad, label_grad = tf.gradients(
                FLAGS.temperature * energy_noise, [x_mod, LABEL_SPLIT[j]])
            energy_noise_old = energy_noise

            lr = FLAGS.step_lr

            if FLAGS.proj_norm != 0.0:
                if FLAGS.proj_norm_type == 'l2':
                    x_grad = tf.clip_by_norm(x_grad, FLAGS.proj_norm)
                elif FLAGS.proj_norm_type == 'li':
                    x_grad = tf.clip_by_value(
                        x_grad, -FLAGS.proj_norm, FLAGS.proj_norm)
                else:
                    print("Other types of projection are not supported!!!")
                    assert False

            # Clip gradient norm for now
            if FLAGS.hmc:
                # Step size should be tuned to get around 65% acceptance
                def energy(x):
                    return FLAGS.temperature * \
                        model.forward(x, weights[0], label=LABEL_SPLIT[j], reuse=True)

                x_last = hmc(x_mod, 15., 10, energy)
            else:
                x_last = x_mod - (lr) * x_grad

            x_mod = x_last
            x_mod = tf.clip_by_value(x_mod, 0, FLAGS.rescale)

            counter = counter + 1

            return counter, x_mod

        steps, x_mod = tf.while_loop(c, langevin_step, (steps, x_mod))

        energy_eval = model.forward(x_mod, weights[0], label=LABEL_SPLIT[j],
                                    stop_at_grad=False, reuse=True)
        x_grad = tf.gradients(FLAGS.temperature * energy_eval, [x_mod])[0]
        x_grads.append(x_grad)

        energy_negs.append(
            model.forward(
                tf.stop_gradient(x_mod),
                weights[0],
                label=LABEL_SPLIT[j],
                stop_at_grad=False,
                reuse=True))

        test_x_mod = x_mod

        temp = FLAGS.temperature

        energy_neg = energy_negs[-1]
        x_off = tf.reduce_mean(
            tf.abs(x_mod[:tf.shape(X_SPLIT[j])[0]] - X_SPLIT[j]))

        loss_energy = model.forward(
            x_mod,
            weights[0],
            reuse=True,
            label=LABEL,
            stop_grad=True)

        print("Finished processing loop construction ...")

        target_vars = {}

        if FLAGS.cclass or FLAGS.model_cclass:
            label_sum = tf.reduce_sum(LABEL_SPLIT[0], axis=0)
            label_prob = label_sum / tf.reduce_sum(label_sum)
            label_ent = -tf.reduce_sum(label_prob *
                                       tf.math.log(label_prob + 1e-7))
        else:
            label_ent = tf.zeros(1)

        target_vars['label_ent'] = label_ent

        if FLAGS.train:

            if FLAGS.objective == 'logsumexp':
                pos_term = temp * energy_pos
                energy_neg_reduced = (energy_neg - tf.reduce_min(energy_neg))
                coeff = tf.stop_gradient(tf.exp(-temp * energy_neg_reduced))
                norm_constant = tf.stop_gradient(tf.reduce_sum(coeff)) + 1e-4
                pos_loss = tf.reduce_mean(temp * energy_pos)
                neg_loss = coeff * (-1 * temp * energy_neg) / norm_constant
                loss_ml = FLAGS.ml_coeff * (pos_loss + tf.reduce_sum(neg_loss))
            elif FLAGS.objective == 'cd':
                pos_loss = tf.reduce_mean(temp * energy_pos)
                neg_loss = -tf.reduce_mean(temp * energy_neg)
                loss_ml = FLAGS.ml_coeff * (pos_loss + tf.reduce_sum(neg_loss))
            elif FLAGS.objective == 'softplus':
                loss_ml = FLAGS.ml_coeff * \
                    tf.nn.softplus(temp * (energy_pos - energy_neg))

            loss_total = tf.reduce_mean(loss_ml)

            if not FLAGS.zero_kl:
                loss_total = loss_total + tf.reduce_mean(loss_energy)

            loss_total = loss_total + \
                FLAGS.l2_coeff * (tf.reduce_mean(tf.square(energy_pos)) + tf.reduce_mean(tf.square((energy_neg))))

            print("Started gradient computation...")
            gvs = optimizer.compute_gradients(loss_total)
            gvs = [(k, v) for (k, v) in gvs if k is not None]

            print("Applying gradients...")

            tower_grads.append(gvs)

            print("Finished applying gradients.")

            target_vars['loss_ml'] = loss_ml
            target_vars['total_loss'] = loss_total
            target_vars['loss_energy'] = loss_energy
            target_vars['weights'] = weights
            target_vars['gvs'] = gvs

        target_vars['X'] = X
        target_vars['Y'] = Y
        target_vars['LABEL'] = LABEL
        target_vars['LABEL_POS'] = LABEL_POS
        target_vars['X_NOISE'] = X_NOISE
        target_vars['energy_pos'] = energy_pos
        target_vars['energy_start'] = energy_negs[0]

        if len(x_grads) >= 1:
            target_vars['x_grad'] = x_grads[-1]
            target_vars['x_grad_first'] = x_grads[0]
        else:
            target_vars['x_grad'] = tf.zeros(1)
            target_vars['x_grad_first'] = tf.zeros(1)

        target_vars['x_mod'] = x_mod
        target_vars['x_off'] = x_off
        target_vars['temp'] = temp
        target_vars['energy_neg'] = energy_neg
        target_vars['test_x_mod'] = test_x_mod
        target_vars['eps_begin'] = eps_begin

    if FLAGS.train:
        grads = average_gradients(tower_grads)
        train_op = optimizer.apply_gradients(grads)
        target_vars['train_op'] = train_op

    config = tf.ConfigProto()

    if hvd.size() > 1:
        config.gpu_options.visible_device_list = str(hvd.local_rank())

    sess = tf.Session(config=config)

    saver = loader = tf.train.Saver(
        max_to_keep=30, keep_checkpoint_every_n_hours=6)

    total_parameters = 0
    for variable in tf.trainable_variables():
        # shape is an array of tf.Dimension
        shape = variable.get_shape()
        variable_parameters = 1
        for dim in shape:
            variable_parameters *= dim.value
        total_parameters += variable_parameters
    print("Model has a total of {} parameters".format(total_parameters))

    sess.run(tf.global_variables_initializer())

    resume_itr = 0

    if (FLAGS.resume_iter != -1 or not FLAGS.train) and hvd.rank() == 0:
        model_file = osp.join(logdir, 'model_{}'.format(FLAGS.resume_iter))
        resume_itr = FLAGS.resume_iter
        # saver.restore(sess, model_file)
        optimistic_restore(sess, model_file)

    sess.run(hvd.broadcast_global_variables(0))
    print("Initializing variables...")

    print("Start broadcast")
    print("End broadcast")

    if FLAGS.train:
        train(target_vars, saver, sess,
              logger, data_loader, resume_itr,
              logdir)

    test(target_vars, saver, sess, logger, data_loader)