Exemplo n.º 1
0
def main(args):
    # load textfile
    train_dataset, dev_dataset, test_dataset, vocab, vocab_inv = read_data(
        args.text_filename,
        train_split_ratio=args.train_split,
        dev_split_ratio=args.dev_split,
        seed=args.seed)
    save_vocab(args.model_dir, vocab, vocab_inv)
    vocab_size = len(vocab)
    print_bold("data	#	hash")
    print("train	{}	{}".format(len(train_dataset), hash(str(train_dataset))))
    print("dev	{}	{}".format(len(dev_dataset), hash(str(dev_dataset))))
    print("test	{}	{}".format(len(test_dataset), hash(str(test_dataset))))
    print("vocab	{}".format(vocab_size))

    # split into buckets
    train_buckets = make_buckets(train_dataset)

    print_bold("buckets	#data	(train)")
    if args.buckets_limit is not None:
        train_buckets = train_buckets[:args.buckets_limit + 1]
    for size, data in zip(bucket_sizes, train_buckets):
        print("{}	{}".format(size, len(data)))

    print_bold("buckets	#data	(dev)")
    dev_buckets = make_buckets(dev_dataset)
    if args.buckets_limit is not None:
        dev_buckets = dev_buckets[:args.buckets_limit + 1]
    for size, data in zip(bucket_sizes, dev_buckets):
        print("{}	{}".format(size, len(data)))

    print_bold("buckets	#data	(test)")
    test_buckets = make_buckets(test_dataset)
    for size, data in zip(bucket_sizes, test_buckets):
        print("{}	{}".format(size, len(data)))

    # to maintain equilibrium
    min_num_data = 0
    for data in train_buckets:
        if min_num_data == 0 or len(data) < min_num_data:
            min_num_data = len(data)
    repeats = []
    for data in train_buckets:
        repeat = len(data) // min_num_data
        repeat = repeat + 1 if repeat == 0 else repeat
        repeats.append(repeat)

    num_updates_per_iteration = 0
    for repeat, data in zip(repeats, train_buckets):
        num_updates_per_iteration += repeat * args.batchsize
    num_iteration = len(train_dataset) // num_updates_per_iteration + 1

    # init
    model = load_model(args.model_dir)
    if model is None:
        model = RNNModel(vocab_size,
                         args.ndim_embedding,
                         args.num_layers,
                         ndim_h=args.ndim_h,
                         kernel_size=args.kernel_size,
                         pooling=args.pooling,
                         zoneout=args.zoneout,
                         dropout=args.dropout,
                         wgain=args.wgain,
                         densely_connected=args.densely_connected,
                         ignore_label=ID_PAD)
    if args.gpu_device >= 0:
        chainer.cuda.get_device(args.gpu_device).use()
        model.to_gpu()

    # setup an optimizer
    if args.eve:
        optimizer = Eve(alpha=args.learning_rate, beta1=0.9)
    else:
        optimizer = optimizers.Adam(alpha=args.learning_rate, beta1=0.9)
    optimizer.setup(model)
    optimizer.add_hook(chainer.optimizer.GradientClipping(args.grad_clip))
    optimizer.add_hook(chainer.optimizer.WeightDecay(args.weight_decay))
    min_learning_rate = 1e-7
    prev_ppl = None
    total_time = 0

    def mean(l):
        return sum(l) / len(l)

    # training
    for epoch in xrange(1, args.epoch + 1):
        print("Epoch", epoch)
        start_time = time.time()
        for itr in xrange(1, num_iteration + 1):
            sys.stdout.write("\r{} / {}".format(itr, num_iteration))
            sys.stdout.flush()

            for repeat, dataset in zip(repeats, train_buckets):
                for r in xrange(repeat):
                    batch = sample_batch_from_bucket(dataset, args.batchsize)
                    source, target = make_source_target_pair(batch)
                    if model.xp is cuda.cupy:
                        source = cuda.to_gpu(source)
                        target = cuda.to_gpu(target)
                    model.reset_state()
                    Y = model(source)
                    loss = softmax_cross_entropy(Y,
                                                 target,
                                                 ignore_label=ID_PAD)
                    optimizer.update(lossfun=lambda: loss)

            if itr % args.interval == 0 or itr == num_iteration:
                save_model(args.model_dir, model)

        # show log
        sys.stdout.write("\r" + stdout.CLEAR)
        sys.stdout.flush()
        print_bold("	accuracy (sampled train)")
        acc_train = compute_random_accuracy(model, train_buckets,
                                            args.batchsize)
        print("	", mean(acc_train), acc_train)
        print_bold("	accuracy (dev)")
        acc_dev = compute_accuracy(model, dev_buckets, args.batchsize)
        print("	", mean(acc_dev), acc_dev)
        print_bold("	ppl (sampled train)")
        ppl_train = compute_random_perplexity(model, train_buckets,
                                              args.batchsize)
        print("	", mean(ppl_train), ppl_train)
        print_bold("	ppl (dev)")
        ppl_dev = compute_perplexity(model, dev_buckets, args.batchsize)
        ppl_dev_mean = mean(ppl_dev)
        print("	", ppl_dev_mean, ppl_dev)
        elapsed_time = (time.time() - start_time) / 60.
        total_time += elapsed_time
        print("	done in {} min, lr = {}, total {} min".format(
            int(elapsed_time), optimizer.alpha, int(total_time)))

        # decay learning rate
        if prev_ppl is not None and ppl_dev_mean >= prev_ppl and optimizer.alpha > min_learning_rate:
            optimizer.alpha *= 0.5
        prev_ppl = ppl_dev_mean
Exemplo n.º 2
0
def main():
	# load textfile
	dataset_train, dataset_dev, _, vocab, vocab_inv = read_data(args.train_filename, args.dev_filename)
	vocab_size = len(vocab)

	save_vocab(args.model_dir, vocab, vocab_inv)

	# split into buckets
	train_buckets = make_buckets(dataset_train)

	if args.buckets_slice is not None:
		train_buckets = train_buckets[:args.buckets_slice + 1]

	dev_buckets = None
	if len(dataset_dev) > 0:
		dev_buckets = make_buckets(dataset_dev)
		if args.buckets_slice is not None:
			dev_buckets = dev_buckets[:args.buckets_slice + 1]

	# print
	dump_dataset(dataset_train, dataset_dev, train_buckets, dev_buckets, vocab_size)

	# to maintain equilibrium
	required_interations = []
	for data in train_buckets:
		itr = math.ceil(len(data) / args.batchsize)
		required_interations.append(itr)
	total_iterations = sum(required_interations)
	buckets_distribution = np.asarray(required_interations, dtype=float) / total_iterations

	# init
	model = load_model(args.model_dir)
	if model is None:
		model = RNNModel(vocab_size, args.ndim_embedding, args.num_layers, ndim_h=args.ndim_h, kernel_size=args.kernel_size, pooling=args.pooling, zoneout=args.zoneout, dropout=args.dropout, weightnorm=args.weightnorm, wgain=args.wgain, densely_connected=args.densely_connected, ignore_label=ID_PAD)

	if args.gpu_device >= 0:
		chainer.cuda.get_device(args.gpu_device).use()
		model.to_gpu()

	# setup an optimizer
	optimizer = get_optimizer(args.optimizer, args.learning_rate, args.momentum)
	optimizer.setup(model)
	optimizer.add_hook(chainer.optimizer.GradientClipping(args.grad_clip))
	optimizer.add_hook(chainer.optimizer.WeightDecay(args.weight_decay))
	final_learning_rate = 1e-4
	total_time = 0

	def mean(l):
		return sum(l) / len(l)

	# training
	for epoch in range(1, args.epoch + 1):
		print("Epoch", epoch)
		start_time = time.time()

		with chainer.using_config("train", True):
			for itr in range(total_iterations):
				bucket_idx = int(np.random.choice(np.arange(len(train_buckets)), size=1, p=buckets_distribution))
				dataset = train_buckets[bucket_idx]
				np.random.shuffle(dataset)
				data_batch = dataset[:args.batchsize]

				source_batch, target_batch = make_source_target_pair(data_batch)

				if args.gpu_device >= 0:
					source_batch = cuda.to_gpu(source_batch)
					target_batch = cuda.to_gpu(target_batch)

				# update params
				model.reset_state()
				y_batch = model(source_batch)
				loss = F.softmax_cross_entropy(y_batch, target_batch, ignore_label=ID_PAD)
				optimizer.update(lossfun=lambda: loss)

				# show log
				printr("iteration {}/{}".format(itr + 1, total_iterations))

		save_model(args.model_dir, model)

		# clear console
		printr("")

		# compute perplexity
		with chainer.using_config("train", False):
			if dev_buckets is not None:
				printb("	ppl (dev)")
				ppl_dev = compute_perplexity(model, dev_buckets, args.batchsize)
				print("	", mean(ppl_dev), ppl_dev)

		# show log
		elapsed_time = (time.time() - start_time) / 60.
		total_time += elapsed_time
		print("	done in {} min, lr = {}, total {} min".format(int(elapsed_time), get_current_learning_rate(optimizer), int(total_time)))

		# decay learning rate
		decay_learning_rate(optimizer, args.lr_decay_factor, final_learning_rate)