def test_sampling():

    # Create Theano variables
    sampling_input = theano.tensor.lmatrix("input")

    # Construct model
    encoder = BidirectionalEncoder(vocab_size=10, embedding_dim=5, state_dim=8)
    decoder = Decoder(vocab_size=12, embedding_dim=6, state_dim=8, representation_dim=16, theano_seed=1234)
    sampling_representation = encoder.apply(sampling_input, theano.tensor.ones(sampling_input.shape))
    generateds = decoder.generate(sampling_input, sampling_representation)
    model = Model(generateds[1])

    # Initialize model
    encoder.weights_init = decoder.weights_init = IsotropicGaussian(0.01)
    encoder.biases_init = decoder.biases_init = Constant(0)
    encoder.push_initialization_config()
    decoder.push_initialization_config()
    encoder.bidir.prototype.weights_init = Orthogonal()
    decoder.transition.weights_init = Orthogonal()
    encoder.initialize()
    decoder.initialize()

    # Compile a function for the generated
    sampling_fn = model.get_theano_function()

    # Create literal variables
    numpy.random.seed(1234)
    x = numpy.random.randint(0, 10, size=(1, 2))

    # Call function and check result
    generated_step = sampling_fn(x)
    assert len(generated_step[0].flatten()) == 4
def test_search_model():

    # Create Theano variables
    floatX = theano.config.floatX
    source_sentence = theano.tensor.lmatrix("source")
    source_sentence_mask = theano.tensor.matrix("source_mask", dtype=floatX)
    target_sentence = theano.tensor.lmatrix("target")
    target_sentence_mask = theano.tensor.matrix("target_mask", dtype=floatX)

    # Construct model
    encoder = BidirectionalEncoder(vocab_size=10, embedding_dim=5, state_dim=8)
    decoder = Decoder(vocab_size=12, embedding_dim=6, state_dim=8, representation_dim=16)
    cost = decoder.cost(
        encoder.apply(source_sentence, source_sentence_mask),
        source_sentence_mask,
        target_sentence,
        target_sentence_mask,
    )

    # Compile a function for the cost
    f_cost = theano.function(
        inputs=[source_sentence, source_sentence_mask, target_sentence, target_sentence_mask], outputs=cost
    )

    # Create literal variables
    numpy.random.seed(1234)
    x = numpy.random.randint(0, 10, size=(22, 4))
    y = numpy.random.randint(0, 12, size=(22, 6))
    x_mask = numpy.ones_like(x).astype(floatX)
    y_mask = numpy.ones_like(y).astype(floatX)

    # Initialize model
    encoder.weights_init = decoder.weights_init = IsotropicGaussian(0.01)
    encoder.biases_init = decoder.biases_init = Constant(0)
    encoder.push_initialization_config()
    decoder.push_initialization_config()
    encoder.bidir.prototype.weights_init = Orthogonal()
    decoder.transition.weights_init = Orthogonal()
    encoder.initialize()
    decoder.initialize()

    cost_ = f_cost(x, x_mask, y, y_mask)
    assert_allclose(cost_, 14.90944)
Ejemplo n.º 3
0
def create_word_encoder(config):
    encoder = BidirectionalEncoder(config['src_vocab_size'],
                                   config['enc_embed'], config['enc_nhids'])
    encoder.weights_init = IsotropicGaussian(config['weight_scale'])
    encoder.biases_init = Constant(0)
    encoder.push_initialization_config()
    encoder.bidir.prototype.weights_init = Orthogonal()
    encoder.initialize()

    input_words = tensor.lmatrix('words')
    input_words_mask = tensor.matrix('words_mask')
    training_representation = encoder.apply(input_words, input_words_mask)
    training_representation.name = "words_representation"

    sampling_input_words = tensor.lmatrix('sampling_words')
    sampling_input_words_mask = tensor.ones(
        (sampling_input_words.shape[0], sampling_input_words.shape[1]))
    sampling_representation = encoder.apply(sampling_input_words,
                                            sampling_input_words_mask)

    return encoder, training_representation, sampling_representation
Ejemplo n.º 4
0
def main(config, tr_stream, dev_stream):
    # Create Theano variables
    logger.info('Creating theano variables')
    source_char_seq = tensor.lmatrix('source_char_seq')
    source_sample_matrix = tensor.btensor3('source_sample_matrix')
    source_char_aux = tensor.bmatrix('source_char_aux')
    source_word_mask = tensor.bmatrix('source_word_mask')
    target_char_seq = tensor.lmatrix('target_char_seq')
    target_char_aux = tensor.bmatrix('target_char_aux')
    target_char_mask = tensor.bmatrix('target_char_mask')
    target_sample_matrix = tensor.btensor3('target_sample_matrix')
    target_word_mask = tensor.bmatrix('target_word_mask')
    target_resample_matrix = tensor.btensor3('target_resample_matrix')
    target_prev_char_seq = tensor.lmatrix('target_prev_char_seq')
    target_prev_char_aux = tensor.bmatrix('target_prev_char_aux')
    target_bos_idx = tr_stream.trg_bos
    target_space_idx = tr_stream.space_idx['target']

    # Construct model
    logger.info('Building RNN encoder-decoder')

    encoder = BidirectionalEncoder(config['src_vocab_size'],
                                   config['enc_embed'],
                                   config['src_dgru_nhids'],
                                   config['enc_nhids'],
                                   config['src_dgru_depth'],
                                   config['bidir_encoder_depth'])

    decoder = Decoder(config['trg_vocab_size'], config['dec_embed'],
                      config['trg_dgru_nhids'], config['trg_igru_nhids'],
                      config['dec_nhids'], config['enc_nhids'] * 2,
                      config['transition_depth'], config['trg_igru_depth'],
                      config['trg_dgru_depth'], target_space_idx,
                      target_bos_idx)

    representation = encoder.apply(source_char_seq, source_sample_matrix,
                                   source_char_aux, source_word_mask)
    cost = decoder.cost(representation, source_word_mask, target_char_seq,
                        target_sample_matrix, target_resample_matrix,
                        target_char_aux, target_char_mask, target_word_mask,
                        target_prev_char_seq, target_prev_char_aux)

    logger.info('Creating computational graph')
    cg = ComputationGraph(cost)

    # Initialize model
    logger.info('Initializing model')
    encoder.weights_init = decoder.weights_init = IsotropicGaussian(
        config['weight_scale'])
    encoder.biases_init = decoder.biases_init = Constant(0)
    encoder.push_initialization_config()
    decoder.push_initialization_config()
    for layer_n in range(config['src_dgru_depth']):
        encoder.decimator.dgru.transitions[layer_n].weights_init = Orthogonal()
    for layer_n in range(config['bidir_encoder_depth']):
        encoder.children[
            1 + layer_n].prototype.recurrent.weights_init = Orthogonal()
    if config['trg_igru_depth'] == 1:
        decoder.interpolator.igru.weights_init = Orthogonal()
    else:
        for layer_n in range(config['trg_igru_depth']):
            decoder.interpolator.igru.transitions[
                layer_n].weights_init = Orthogonal()
    for layer_n in range(config['trg_dgru_depth']):
        decoder.interpolator.feedback_brick.dgru.transitions[
            layer_n].weights_init = Orthogonal()
    for layer_n in range(config['transition_depth']):
        decoder.transition.transitions[layer_n].weights_init = Orthogonal()
    encoder.initialize()
    decoder.initialize()

    # Print shapes
    shapes = [param.get_value().shape for param in cg.parameters]
    logger.info("Parameter shapes: ")
    for shape, count in Counter(shapes).most_common():
        logger.info('    {:15}: {}'.format(str(shape), count))
    logger.info("Total number of parameters: {}".format(len(shapes)))

    # Print parameter names
    enc_dec_param_dict = merge(
        Selector(encoder).get_parameters(),
        Selector(decoder).get_parameters())
    logger.info("Parameter names: ")
    for name, value in enc_dec_param_dict.items():
        logger.info('    {:15}: {}'.format(str(value.get_value().shape), name))
    logger.info("Total number of parameters: {}".format(
        len(enc_dec_param_dict)))

    # Set up training model
    logger.info("Building model")
    training_model = Model(cost)
    # Set up training algorithm
    logger.info("Initializing training algorithm")
    algorithm = GradientDescent(cost=cost,
                                parameters=cg.parameters,
                                step_rule=CompositeRule([
                                    StepClipping(config['step_clipping']),
                                    eval(config['step_rule'])()
                                ]))

    # Set extensions
    logger.info("Initializing extensions")
    # Extensions
    gradient_norm = aggregation.mean(algorithm.total_gradient_norm)
    step_norm = aggregation.mean(algorithm.total_step_norm)
    train_monitor = CostCurve([cost, gradient_norm, step_norm],
                              config=config,
                              after_batch=True,
                              before_first_epoch=True,
                              prefix='tra')
    extensions = [
        train_monitor,
        Timing(),
        Printing(every_n_batches=config['print_freq']),
        FinishAfter(after_n_batches=config['finish_after']),
        CheckpointNMT(config['saveto'], every_n_batches=config['save_freq'])
    ]

    # Set up beam search and sampling computation graphs if necessary
    if config['hook_samples'] >= 1 or config['bleu_script'] is not None:
        logger.info("Building sampling model")
        generated = decoder.generate(representation, source_word_mask)
        search_model = Model(generated)
        _, samples = VariableFilter(
            bricks=[decoder.sequence_generator], name="outputs")(
                ComputationGraph(generated[config['transition_depth']])
            )  # generated[transition_depth] is next_outputs

    # Add sampling
    if config['hook_samples'] >= 1:
        logger.info("Building sampler")
        extensions.append(
            Sampler(model=search_model,
                    data_stream=tr_stream,
                    hook_samples=config['hook_samples'],
                    transition_depth=config['transition_depth'],
                    every_n_batches=config['sampling_freq'],
                    src_vocab_size=config['src_vocab_size']))

    # Add early stopping based on bleu
    if config['bleu_script'] is not None:
        logger.info("Building bleu validator")
        extensions.append(
            BleuValidator(source_char_seq,
                          source_sample_matrix,
                          source_char_aux,
                          source_word_mask,
                          samples=samples,
                          config=config,
                          model=search_model,
                          data_stream=dev_stream,
                          normalize=config['normalized_bleu'],
                          every_n_batches=config['bleu_val_freq']))

    # Reload model if necessary
    if config['reload']:
        extensions.append(LoadNMT(config['saveto']))

    # Initialize main loop
    logger.info("Initializing main loop")
    main_loop = MainLoop(model=training_model,
                         algorithm=algorithm,
                         data_stream=tr_stream,
                         extensions=extensions)

    # Train!
    main_loop.run()
Ejemplo n.º 5
0
def main(mode, config, use_bokeh=False):

    # Construct model
    logger.info('Building RNN encoder-decoder')
    encoder = BidirectionalEncoder(config['src_vocab_size'],
                                   config['enc_embed'], config['enc_nhids'])
    decoder = Decoder(config['trg_vocab_size'], config['dec_embed'],
                      config['dec_nhids'], config['enc_nhids'] * 2,
                      config['topical_embedding_dim'])
    topical_transformer = topicalq_transformer(config['topical_vocab_size'],
                                               config['topical_embedding_dim'],
                                               config['enc_nhids'],
                                               config['topical_word_num'],
                                               config['batch_size'])

    if mode == "train":

        # Create Theano variables
        logger.info('Creating theano variables')
        source_sentence = tensor.lmatrix('source')
        source_sentence_mask = tensor.matrix('source_mask')
        target_sentence = tensor.lmatrix('target')
        target_sentence_mask = tensor.matrix('target_mask')
        sampling_input = tensor.lmatrix('input')
        source_topical_word = tensor.lmatrix('source_topical')
        source_topical_mask = tensor.matrix('source_topical_mask')

        # Get training and development set streams
        tr_stream = get_tr_stream_with_topicalq(**config)
        dev_stream = get_dev_stream_with_topicalq(**config)
        topic_embedding = topical_transformer.apply(source_topical_word)
        # Get cost of the model
        representation = encoder.apply(source_sentence, source_sentence_mask)
        tw_representation = topical_transformer.look_up.apply(
            source_topical_word.T)
        content_embedding = representation[0, :,
                                           (representation.shape[2] / 2):]

        cost = decoder.cost(representation, source_sentence_mask,
                            tw_representation, source_topical_mask,
                            target_sentence, target_sentence_mask,
                            topic_embedding, content_embedding)

        logger.info('Creating computational graph')
        cg = ComputationGraph(cost)

        # Initialize model
        logger.info('Initializing model')
        encoder.weights_init = decoder.weights_init = IsotropicGaussian(
            config['weight_scale'])
        encoder.biases_init = decoder.biases_init = Constant(0)
        encoder.push_initialization_config()
        decoder.push_initialization_config()
        encoder.bidir.prototype.weights_init = Orthogonal()
        decoder.transition.weights_init = Orthogonal()
        encoder.initialize()
        decoder.initialize()
        topical_transformer.weights_init = IsotropicGaussian(
            config['weight_scale'])
        topical_transformer.biases_init = Constant(0)
        topical_transformer.push_allocation_config()
        #don't know whether the initialize is for
        topical_transformer.look_up.weights_init = Orthogonal()
        topical_transformer.transformer.weights_init = Orthogonal()
        topical_transformer.initialize()
        word_topical_embedding = cPickle.load(
            open(config['topical_embeddings'], 'rb'))
        np_word_topical_embedding = numpy.array(word_topical_embedding,
                                                dtype='float32')
        topical_transformer.look_up.W.set_value(np_word_topical_embedding)
        topical_transformer.look_up.W.tag.role = []

        # apply dropout for regularization
        if config['dropout'] < 1.0:
            # dropout is applied to the output of maxout in ghog
            logger.info('Applying dropout')
            dropout_inputs = [
                x for x in cg.intermediary_variables
                if x.name == 'maxout_apply_output'
            ]
            cg = apply_dropout(cg, dropout_inputs, config['dropout'])

        # Apply weight noise for regularization
        if config['weight_noise_ff'] > 0.0:
            logger.info('Applying weight noise to ff layers')
            enc_params = Selector(encoder.lookup).get_params().values()
            enc_params += Selector(encoder.fwd_fork).get_params().values()
            enc_params += Selector(encoder.back_fork).get_params().values()
            dec_params = Selector(
                decoder.sequence_generator.readout).get_params().values()
            dec_params += Selector(
                decoder.sequence_generator.fork).get_params().values()
            dec_params += Selector(decoder.state_init).get_params().values()
            cg = apply_noise(cg, enc_params + dec_params,
                             config['weight_noise_ff'])

        # Print shapes
        shapes = [param.get_value().shape for param in cg.parameters]
        logger.info("Parameter shapes: ")
        for shape, count in Counter(shapes).most_common():
            logger.info('    {:15}: {}'.format(shape, count))
        logger.info("Total number of parameters: {}".format(len(shapes)))

        # Print parameter names
        enc_dec_param_dict = merge(
            Selector(encoder).get_parameters(),
            Selector(decoder).get_parameters())
        logger.info("Parameter names: ")
        for name, value in enc_dec_param_dict.items():
            logger.info('    {:15}: {}'.format(value.get_value().shape, name))
        logger.info("Total number of parameters: {}".format(
            len(enc_dec_param_dict)))

        # Set up training model
        logger.info("Building model")
        training_model = Model(cost)

        # Set extensions
        logger.info("Initializing extensions")
        extensions = [
            FinishAfter(after_n_batches=config['finish_after']),
            TrainingDataMonitoring([cost], after_batch=True),
            Printing(after_batch=True),
            CheckpointNMT(config['saveto'],
                          every_n_batches=config['save_freq'])
        ]
        '''
        # Set up beam search and sampling computation graphs if necessary
        if config['hook_samples'] >= 1 or config['bleu_script'] is not None:
            logger.info("Building sampling model")
            sampling_representation = encoder.apply(
                sampling_input, tensor.ones(sampling_input.shape))
            generated = decoder.generate(
                sampling_input, sampling_representation)
            search_model = Model(generated)
            _, samples = VariableFilter(
                bricks=[decoder.sequence_generator], name="outputs")(
                    ComputationGraph(generated[1]))

        # Add sampling
        if config['hook_samples'] >= 1:
            logger.info("Building sampler")
            extensions.append(
                Sampler(model=search_model, data_stream=tr_stream,
                        hook_samples=config['hook_samples'],
                        every_n_batches=config['sampling_freq'],
                        src_vocab_size=config['src_vocab_size']))

        # Add early stopping based on bleu
        if config['bleu_script'] is not None:
            logger.info("Building bleu validator")
            extensions.append(
                BleuValidator(sampling_input, samples=samples, config=config,
                              model=search_model, data_stream=dev_stream,
                              normalize=config['normalized_bleu'],
                              every_n_batches=config['bleu_val_freq']))
        '''

        # Reload model if necessary
        if config['reload']:
            extensions.append(LoadNMT(config['saveto']))

        # Plot cost in bokeh if necessary
        if use_bokeh and BOKEH_AVAILABLE:
            extensions.append(
                Plot('Cs-En',
                     channels=[['decoder_cost_cost']],
                     after_batch=True))

        # Set up training algorithm
        logger.info("Initializing training algorithm")
        algorithm = GradientDescent(cost=cost,
                                    parameters=cg.parameters,
                                    on_unused_sources='warn',
                                    step_rule=CompositeRule([
                                        StepClipping(config['step_clipping']),
                                        eval(config['step_rule'])()
                                    ]))

        # Initialize main loop
        logger.info("Initializing main loop")
        main_loop = MainLoop(model=training_model,
                             algorithm=algorithm,
                             data_stream=tr_stream,
                             extensions=extensions)

        # Train!
        main_loop.run()

    elif mode == 'translate':

        # Create Theano variables
        logger.info('Creating theano variables')
        source_sentence = tensor.lmatrix('source')
        source_topical_word = tensor.lmatrix('source_topical')

        # Get test set stream
        test_stream = get_dev_stream_with_topicalq(
            config['test_set'], config['src_vocab'], config['src_vocab_size'],
            config['topical_test_set'], config['topical_vocab'],
            config['topical_vocab_size'], config['unk_id'])
        ftrans = open(config['test_set'] + '.trans.out', 'w')

        # Helper utilities
        sutils = SamplingBase()
        unk_idx = config['unk_id']
        src_eos_idx = config['src_vocab_size'] - 1
        trg_eos_idx = config['trg_vocab_size'] - 1

        # Get beam search
        logger.info("Building sampling model")
        topic_embedding = topical_transformer.apply(source_topical_word)
        representation = encoder.apply(source_sentence,
                                       tensor.ones(source_sentence.shape))
        tw_representation = topical_transformer.look_up.apply(
            source_topical_word.T)
        content_embedding = representation[0, :,
                                           (representation.shape[2] / 2):]
        generated = decoder.generate(source_sentence,
                                     representation,
                                     tw_representation,
                                     topical_embedding=topic_embedding,
                                     content_embedding=content_embedding)

        _, samples = VariableFilter(
            bricks=[decoder.sequence_generator], name="outputs")(
                ComputationGraph(generated[1]))  # generated[1] is next_outputs
        beam_search = BeamSearch(samples=samples)

        logger.info("Loading the model..")
        model = Model(generated)
        loader = LoadNMT(config['saveto'])
        loader.set_model_parameters(model, loader.load_parameters())

        # Get target vocabulary
        trg_vocab = _ensure_special_tokens(pickle.load(
            open(config['trg_vocab'], 'rb')),
                                           bos_idx=0,
                                           eos_idx=trg_eos_idx,
                                           unk_idx=unk_idx)
        trg_ivocab = {v: k for k, v in trg_vocab.items()}

        logger.info("Started translation: ")
        total_cost = 0.0

        for i, line in enumerate(test_stream.get_epoch_iterator()):

            seq = sutils._oov_to_unk(line[0], config['src_vocab_size'],
                                     unk_idx)
            seq2 = line[1]
            input_ = numpy.tile(seq, (config['beam_size'], 1))
            input_topical = numpy.tile(seq2, (config['beam_size'], 1))

            # draw sample, checking to ensure we don't get an empty string back
            trans, costs = \
                beam_search.search(
                    input_values={source_sentence: input_,source_topical_word:input_topical},
                    max_length=10*len(seq), eol_symbol=src_eos_idx,
                    ignore_first_eol=True)
            '''
            # normalize costs according to the sequence lengths
            if config['normalized_bleu']:
                lengths = numpy.array([len(s) for s in trans])
                costs = costs / lengths
            '''
            #best = numpy.argsort(costs)[0]
            best = numpy.argsort(costs)[0:config['beam_size']]
            for b in best:
                try:
                    total_cost += costs[b]
                    trans_out = trans[b]

                    # convert idx to words
                    trans_out = sutils._idx_to_word(trans_out, trg_ivocab)

                except ValueError:
                    logger.info(
                        "Can NOT find a translation for line: {}".format(i +
                                                                         1))
                    trans_out = '<UNK>'

                print(trans_out, file=ftrans)

            if i != 0 and i % 100 == 0:
                logger.info("Translated {} lines of test set...".format(i))

        logger.info("Total cost of the test: {}".format(total_cost))
        ftrans.close()
    elif mode == 'rerank':
        # Create Theano variables
        ftrans = open(config['val_set'] + '.scores.out', 'w')
        logger.info('Creating theano variables')
        source_sentence = tensor.lmatrix('source')
        source_sentence_mask = tensor.matrix('source_mask')
        target_sentence = tensor.lmatrix('target')
        target_sentence_mask = tensor.matrix('target_mask')

        config['src_data'] = config['val_set']
        config['trg_data'] = config['val_set_grndtruth']
        config['batch_size'] = 1
        config['sort_k_batches'] = 1
        test_stream = get_tr_stream_unsorted(**config)
        logger.info("Building sampling model")
        representations = encoder.apply(source_sentence, source_sentence_mask)
        costs = decoder.cost(representations, source_sentence_mask,
                             target_sentence, target_sentence_mask)
        logger.info("Loading the model..")
        model = Model(costs)
        loader = LoadNMT(config['saveto'])
        loader.set_model_parameters(model, loader.load_parameters())

        costs_computer = function([
            source_sentence, source_sentence_mask, target_sentence,
            target_sentence_mask
        ], costs)
        iterator = test_stream.get_epoch_iterator()

        scores = []
        for i, (src, src_mask, trg, trg_mask) in enumerate(iterator):
            costs = costs_computer(*[src, src_mask, trg, trg_mask])
            cost = costs.sum()
            print(i, cost)
            scores.append(cost)
            ftrans.write(str(cost) + "\n")
        ftrans.close()
Ejemplo n.º 6
0
def main(mode, config, use_bokeh=False):

    # Construct model
    logger.info('Building RNN encoder-decoder')
    encoder = BidirectionalEncoder(config['src_vocab_size'],
                                   config['enc_embed'], config['enc_nhids'])
    topical_transformer = topicalq_transformer(
        config['source_topic_vocab_size'], config['topical_embedding_dim'],
        config['enc_nhids'], config['topical_word_num'], config['batch_size'])
    decoder = Decoder(vocab_size=config['trg_vocab_size'],
                      topicWord_size=config['trg_topic_vocab_size'],
                      embedding_dim=config['dec_embed'],
                      topical_dim=config['topical_embedding_dim'],
                      state_dim=config['dec_nhids'],
                      representation_dim=config['enc_nhids'] * 2,
                      match_function=config['match_function'],
                      use_doubly_stochastic=config['use_doubly_stochastic'],
                      lambda_ds=config['lambda_ds'],
                      use_local_attention=config['use_local_attention'],
                      window_size=config['window_size'],
                      use_step_decay_cost=config['use_step_decay_cost'],
                      use_concentration_cost=config['use_concentration_cost'],
                      lambda_ct=config['lambda_ct'],
                      use_stablilizer=config['use_stablilizer'],
                      lambda_st=config['lambda_st'])
    # here attended dim (representation_dim) of decoder is 2*enc_nhinds
    # because the context given by the encoder is a bidirectional context

    if mode == "train":

        # Create Theano variables
        logger.info('Creating theano variables')
        source_sentence = tensor.lmatrix('source')
        source_sentence_mask = tensor.matrix('source_mask')
        target_sentence = tensor.lmatrix('target')
        target_sentence_mask = tensor.matrix('target_mask')
        target_topic_sentence = tensor.lmatrix('target_topic')
        target_topic_binary_sentence = tensor.lmatrix('target_binary_topic')
        #target_topic_sentence_mask=tensor.lmatrix('target_topic_mask');
        sampling_input = tensor.lmatrix('input')
        source_topical_word = tensor.lmatrix('source_topical')
        source_topical_mask = tensor.matrix('source_topical_mask')

        topic_embedding = topical_transformer.apply(source_topical_word)

        # Get training and development set streams
        tr_stream = get_tr_stream_with_topic_target(**config)
        #dev_stream = get_dev_tr_stream_with_topic_target(**config)

        # Get cost of the model
        representations = encoder.apply(source_sentence, source_sentence_mask)
        tw_representation = topical_transformer.look_up.apply(
            source_topical_word.T)
        content_embedding = representations[0, :,
                                            (representations.shape[2] / 2):]
        cost = decoder.cost(representations, source_sentence_mask,
                            tw_representation, source_topical_mask,
                            target_sentence, target_sentence_mask,
                            target_topic_sentence,
                            target_topic_binary_sentence, topic_embedding,
                            content_embedding)

        logger.info('Creating computational graph')
        perplexity = tensor.exp(cost)
        perplexity.name = 'perplexity'

        cg = ComputationGraph(cost)
        costs_computer = function([
            target_sentence, target_sentence_mask, source_sentence,
            source_sentence_mask, source_topical_word, target_topic_sentence,
            target_topic_binary_sentence
        ], (perplexity),
                                  on_unused_input='ignore')

        # Initialize model
        logger.info('Initializing model')
        encoder.weights_init = decoder.weights_init = IsotropicGaussian(
            config['weight_scale'])
        encoder.biases_init = decoder.biases_init = Constant(0)
        encoder.push_initialization_config()
        decoder.push_initialization_config()
        encoder.bidir.prototype.weights_init = Orthogonal()
        decoder.transition.weights_init = Orthogonal()
        encoder.initialize()
        decoder.initialize()

        topical_transformer.weights_init = IsotropicGaussian(
            config['weight_scale'])
        topical_transformer.biases_init = Constant(0)
        topical_transformer.push_allocation_config()
        #don't know whether the initialize is for
        topical_transformer.look_up.weights_init = Orthogonal()
        topical_transformer.transformer.weights_init = Orthogonal()
        topical_transformer.initialize()
        word_topical_embedding = cPickle.load(
            open(config['topical_embeddings'], 'rb'))
        np_word_topical_embedding = numpy.array(word_topical_embedding,
                                                dtype='float32')
        topical_transformer.look_up.W.set_value(np_word_topical_embedding)
        topical_transformer.look_up.W.tag.role = []

        # apply dropout for regularization
        if config['dropout'] < 1.0:
            # dropout is applied to the output of maxout in ghog
            logger.info('Applying dropout')
            dropout_inputs = [
                x for x in cg.intermediary_variables
                if x.name == 'maxout_apply_output'
            ]
            cg = apply_dropout(cg, dropout_inputs, config['dropout'])

        # Apply weight noise for regularization
        if config['weight_noise_ff'] > 0.0:
            logger.info('Applying weight noise to ff layers')
            enc_params = Selector(encoder.lookup).get_params().values()
            enc_params += Selector(encoder.fwd_fork).get_params().values()
            enc_params += Selector(encoder.back_fork).get_params().values()
            dec_params = Selector(
                decoder.sequence_generator.readout).get_params().values()
            dec_params += Selector(
                decoder.sequence_generator.fork).get_params().values()
            dec_params += Selector(decoder.state_init).get_params().values()
            cg = apply_noise(cg, enc_params + dec_params,
                             config['weight_noise_ff'])

        # Print shapes
        shapes = [param.get_value().shape for param in cg.parameters]
        logger.info("Parameter shapes: ")
        for shape, count in Counter(shapes).most_common():
            logger.info('    {:15}: {}'.format(shape, count))
        logger.info("Total number of parameters: {}".format(len(shapes)))

        # Print parameter names
        enc_dec_param_dict = merge(
            Selector(encoder).get_parameters(),
            Selector(decoder).get_parameters())
        logger.info("Parameter names: ")
        for name, value in enc_dec_param_dict.items():
            logger.info('    {:15}: {}'.format(value.get_value().shape, name))
        logger.info("Total number of parameters: {}".format(
            len(enc_dec_param_dict)))

        # Set up training model
        logger.info("Building model")
        training_model = Model(cost)

        # Set extensions
        logger.info("Initializing extensions")
        extensions = [
            FinishAfter(after_n_batches=config['finish_after']),
            TrainingDataMonitoring([perplexity], after_batch=True),
            CheckpointNMT(config['saveto'],
                          config['model_name'],
                          every_n_batches=config['save_freq'])
        ]

        # # Set up beam search and sampling computation graphs if necessary
        # if config['hook_samples'] >= 1 or config['bleu_script'] is not None:
        #     logger.info("Building sampling model")
        #     sampling_representation = encoder.apply(
        #         sampling_input, tensor.ones(sampling_input.shape))
        #     generated = decoder.generate(
        #         sampling_input, sampling_representation)
        #     search_model = Model(generated)
        #     _, samples = VariableFilter(
        #         bricks=[decoder.sequence_generator], name="outputs")(
        #             ComputationGraph(generated[1]))
        #
        # # Add sampling
        # if config['hook_samples'] >= 1:
        #     logger.info("Building sampler")
        #     extensions.append(
        #         Sampler(model=search_model, data_stream=tr_stream,
        #                 model_name=config['model_name'],
        #                 hook_samples=config['hook_samples'],
        #                 every_n_batches=config['sampling_freq'],
        #                 src_vocab_size=config['src_vocab_size']))
        #
        # # Add early stopping based on bleu
        # if False:
        #     logger.info("Building bleu validator")
        #     extensions.append(
        #         BleuValidator(sampling_input, samples=samples, config=config,
        #                       model=search_model, data_stream=dev_stream,
        #                       normalize=config['normalized_bleu'],
        #                       every_n_batches=config['bleu_val_freq'],
        #                       n_best=3,
        #                       track_n_models=6))
        #
        # logger.info("Building perplexity validator")
        # extensions.append(
        #         pplValidation( config=config,
        #                 model=costs_computer, data_stream=dev_stream,
        #                 model_name=config['model_name'],
        #                 every_n_batches=config['sampling_freq']))

        # Plot cost in bokeh if necessary
        if use_bokeh and BOKEH_AVAILABLE:
            extensions.append(
                Plot('Cs-En',
                     channels=[['decoder_cost_cost']],
                     after_batch=True))

        # Reload model if necessary
        if config['reload']:
            extensions.append(LoadNMT(config['saveto']))

        initial_learning_rate = config['initial_learning_rate']
        log_path = os.path.join(config['saveto'], 'log')
        if config['reload'] and os.path.exists(log_path):
            with open(log_path, 'rb') as source:
                log = cPickle.load(source)
                last = max(log.keys()) - 1
                if 'learning_rate' in log[last]:
                    initial_learning_rate = log[last]['learning_rate']

        # Set up training algorithm
        logger.info("Initializing training algorithm")
        algorithm = GradientDescent(cost=cost,
                                    parameters=cg.parameters,
                                    step_rule=CompositeRule([
                                        Scale(initial_learning_rate),
                                        StepClipping(config['step_clipping']),
                                        eval(config['step_rule'])()
                                    ]),
                                    on_unused_sources='ignore')

        _learning_rate = algorithm.step_rule.components[0].learning_rate
        if config['learning_rate_decay']:
            extensions.append(
                LearningRateHalver(record_name='validation_cost',
                                   comparator=lambda x, y: x > y,
                                   learning_rate=_learning_rate,
                                   patience_default=3))
        else:
            extensions.append(OldModelRemover(saveto=config['saveto']))

        if config['learning_rate_grow']:
            extensions.append(
                LearningRateDoubler(record_name='validation_cost',
                                    comparator=lambda x, y: x < y,
                                    learning_rate=_learning_rate,
                                    patience_default=3))

        extensions.append(
            SimplePrinting(config['model_name'], after_batch=True))

        # Initialize main loop
        logger.info("Initializing main loop")
        main_loop = MainLoop(model=training_model,
                             algorithm=algorithm,
                             data_stream=tr_stream,
                             extensions=extensions)

        # Train!
        main_loop.run()

    elif mode == 'translate':

        logger.info('Creating theano variables')
        sampling_input = tensor.lmatrix('source')
        source_topical_word = tensor.lmatrix('source_topical')
        tw_vocab_overlap = tensor.lmatrix('tw_vocab_overlap')
        tw_vocab_overlap_matrix = cPickle.load(
            open(config['tw_vocab_overlap'], 'rb'))
        tw_vocab_overlap_matrix = numpy.array(tw_vocab_overlap_matrix,
                                              dtype='int32')
        #tw_vocab_overlap=shared(tw_vocab_overlap_matrix);

        topic_embedding = topical_transformer.apply(source_topical_word)

        sutils = SamplingBase()
        unk_idx = config['unk_id']
        src_eos_idx = config['src_vocab_size'] - 1
        trg_eos_idx = config['trg_vocab_size'] - 1
        trg_vocab = _ensure_special_tokens(cPickle.load(
            open(config['trg_vocab'], 'rb')),
                                           bos_idx=0,
                                           eos_idx=trg_eos_idx,
                                           unk_idx=unk_idx)
        trg_ivocab = {v: k for k, v in trg_vocab.items()}

        logger.info("Building sampling model")
        sampling_representation = encoder.apply(
            sampling_input, tensor.ones(sampling_input.shape))
        topic_embedding = topical_transformer.apply(source_topical_word)
        tw_representation = topical_transformer.look_up.apply(
            source_topical_word.T)
        content_embedding = sampling_representation[0, :, (
            sampling_representation.shape[2] / 2):]
        generated = decoder.generate(sampling_input,
                                     sampling_representation,
                                     tw_representation,
                                     topical_embedding=topic_embedding,
                                     content_embedding=content_embedding)

        _, samples = VariableFilter(
            bricks=[decoder.sequence_generator], name="outputs")(
                ComputationGraph(generated[1]))  # generated[1] is next_outputs
        beam_search = BeamSearch(samples=samples)

        logger.info("Loading the model..")
        model = Model(generated)
        #loader = LoadNMT(config['saveto'])
        loader = LoadNMT(config['validation_load'])
        loader.set_model_parameters(model, loader.load_parameters_default())

        logger.info("Started translation: ")
        test_stream = get_dev_stream_with_topicalq(**config)
        ts = test_stream.get_epoch_iterator()
        rts = open(config['val_set_source']).readlines()
        ftrans_original = open(config['val_output_orig'], 'w')
        saved_weights = []
        total_cost = 0.0

        pbar = ProgressBar(max_value=len(rts)).start()
        for i, (line, line_raw) in enumerate(zip(ts, rts)):
            trans_in = line_raw.split()
            seq = sutils._oov_to_unk(line[0], config['src_vocab_size'],
                                     unk_idx)
            seq1 = line[1]
            input_topical = numpy.tile(seq1, (config['beam_size'], 1))
            input_ = numpy.tile(seq, (config['beam_size'], 1))

            # draw sample, checking to ensure we don't get an empty string back
            trans, costs, attendeds, weights = \
                beam_search.search(
                    input_values={sampling_input: input_,source_topical_word:input_topical,tw_vocab_overlap:tw_vocab_overlap_matrix},
                    tw_vocab_overlap=tw_vocab_overlap_matrix,
                    max_length=3*len(seq), eol_symbol=trg_eos_idx,
                    ignore_first_eol=True)

            # normalize costs according to the sequence lengths
            if config['normalized_bleu']:
                lengths = numpy.array([len(s) for s in trans])
                costs = costs / lengths

            best = numpy.argsort(costs)[0]
            try:
                total_cost += costs[best]
                trans_out = trans[best]
                weight = weights[best][:, :len(trans_in)]
                trans_out = sutils._idx_to_word(trans_out, trg_ivocab)
            except ValueError:
                logger.info(
                    "Can NOT find a translation for line: {}".format(i + 1))
                trans_out = '<UNK>'

            saved_weights.append(weight)
            print(' '.join(trans_out), file=ftrans_original)
            pbar.update(i + 1)

        pbar.finish()
        logger.info("Total cost of the test: {}".format(total_cost))
        cPickle.dump(saved_weights, open(config['attention_weights'], 'wb'))
        ftrans_original.close()
        # ap = afterprocesser(config)
        # ap.main()

    elif mode == 'score':
        logger.info('Creating theano variables')
        source_sentence = tensor.lmatrix('source')
        source_sentence_mask = tensor.matrix('source_mask')
        target_sentence = tensor.lmatrix('target')
        target_sentence_mask = tensor.matrix('target_mask')
        target_topic_sentence = tensor.lmatrix('target_topic')
        target_topic_binary_sentence = tensor.lmatrix('target_binary_topic')
        source_topical_word = tensor.lmatrix('source_topical')

        topic_embedding = topical_transformer.apply(source_topical_word)
        # Get cost of the model
        representations = encoder.apply(source_sentence, source_sentence_mask)
        costs = decoder.cost(representations, source_sentence_mask,
                             target_sentence, target_sentence_mask,
                             target_topic_sentence,
                             target_topic_binary_sentence, topic_embedding)

        config['batch_size'] = 1
        config['sort_k_batches'] = 1
        # Get test set stream
        test_stream = get_tr_stream_with_topic_target(**config)

        logger.info("Building sampling model")

        logger.info("Loading the model..")
        model = Model(costs)
        loader = LoadNMT(config['validation_load'])
        loader.set_model_parameters(model, loader.load_parameters_default())

        costs_computer = function([
            target_sentence, target_sentence_mask, source_sentence,
            source_sentence_mask, source_topical_word, target_topic_sentence,
            target_topic_binary_sentence
        ], (costs),
                                  on_unused_input='ignore')

        iterator = test_stream.get_epoch_iterator()

        scores = []
        att_weights = []
        for i, (src, src_mask, trg, trg_mask, te, te_mask, tt, tt_mask, tb,
                tb_mask) in enumerate(iterator):
            costs = costs_computer(*[trg, trg_mask, src, src_mask, te, tt, tb])
            cost = costs.sum()
            print(i, cost)
            scores.append(cost)

        print(sum(scores) / 10007)
Ejemplo n.º 7
0
def main(mode, config, use_bokeh=False):

    # Construct model
    logger.info('Building RNN encoder-decoder')
    encoder = BidirectionalEncoder(
        config['src_vocab_size'], config['enc_embed'], config['enc_nhids'])
    decoder = Decoder(
        config['trg_vocab_size'], config['dec_embed'], config['dec_nhids'],
        config['enc_nhids'] * 2,config['topical_embedding_dim'])
    topical_transformer=topicalq_transformer(config['topical_vocab_size'],config['topical_embedding_dim'], config['enc_nhids'],config['topical_word_num'],config['batch_size']);

    if mode == "train":

        # Create Theano variables
        logger.info('Creating theano variables')
        source_sentence = tensor.lmatrix('source')
        source_sentence_mask = tensor.matrix('source_mask')
        target_sentence = tensor.lmatrix('target')
        target_sentence_mask = tensor.matrix('target_mask')
        sampling_input = tensor.lmatrix('input')
        source_topical_word=tensor.lmatrix('source_topical')
        source_topical_mask=tensor.matrix('source_topical_mask')

        # Get training and development set streams
        tr_stream = get_tr_stream_with_topicalq(**config)
        dev_stream = get_dev_stream_with_topicalq(**config)
        topic_embedding=topical_transformer.apply(source_topical_word);
        # Get cost of the model
        representation=encoder.apply(source_sentence, source_sentence_mask);
        tw_representation=topical_transformer.look_up.apply(source_topical_word.T);
        content_embedding=representation[0,:,(representation.shape[2]/2):];

        cost = decoder.cost(
            representation,source_sentence_mask,tw_representation,
            source_topical_mask, target_sentence, target_sentence_mask,topic_embedding,content_embedding);

        logger.info('Creating computational graph')
        cg = ComputationGraph(cost)

        # Initialize model
        logger.info('Initializing model')
        encoder.weights_init = decoder.weights_init = IsotropicGaussian(
            config['weight_scale'])
        encoder.biases_init = decoder.biases_init = Constant(0)
        encoder.push_initialization_config()
        decoder.push_initialization_config()
        encoder.bidir.prototype.weights_init = Orthogonal()
        decoder.transition.weights_init = Orthogonal()
        encoder.initialize()
        decoder.initialize()
        topical_transformer.weights_init=IsotropicGaussian(
            config['weight_scale']);
        topical_transformer.biases_init=Constant(0);
        topical_transformer.push_allocation_config();#don't know whether the initialize is for
        topical_transformer.look_up.weights_init=Orthogonal();
        topical_transformer.transformer.weights_init=Orthogonal();
        topical_transformer.initialize();
        word_topical_embedding=cPickle.load(open(config['topical_embeddings'], 'rb'));
        np_word_topical_embedding=numpy.array(word_topical_embedding,dtype='float32');
        topical_transformer.look_up.W.set_value(np_word_topical_embedding);
        topical_transformer.look_up.W.tag.role=[];


        # apply dropout for regularization
        if config['dropout'] < 1.0:
            # dropout is applied to the output of maxout in ghog
            logger.info('Applying dropout')
            dropout_inputs = [x for x in cg.intermediary_variables
                              if x.name == 'maxout_apply_output']
            cg = apply_dropout(cg, dropout_inputs, config['dropout'])

        # Apply weight noise for regularization
        if config['weight_noise_ff'] > 0.0:
            logger.info('Applying weight noise to ff layers')
            enc_params = Selector(encoder.lookup).get_params().values()
            enc_params += Selector(encoder.fwd_fork).get_params().values()
            enc_params += Selector(encoder.back_fork).get_params().values()
            dec_params = Selector(
                decoder.sequence_generator.readout).get_params().values()
            dec_params += Selector(
                decoder.sequence_generator.fork).get_params().values()
            dec_params += Selector(decoder.state_init).get_params().values()
            cg = apply_noise(
                cg, enc_params+dec_params, config['weight_noise_ff'])

        # Print shapes
        shapes = [param.get_value().shape for param in cg.parameters]
        logger.info("Parameter shapes: ")
        for shape, count in Counter(shapes).most_common():
            logger.info('    {:15}: {}'.format(shape, count))
        logger.info("Total number of parameters: {}".format(len(shapes)))

        # Print parameter names
        enc_dec_param_dict = merge(Selector(encoder).get_parameters(),
                                   Selector(decoder).get_parameters())
        logger.info("Parameter names: ")
        for name, value in enc_dec_param_dict.items():
            logger.info('    {:15}: {}'.format(value.get_value().shape, name))
        logger.info("Total number of parameters: {}"
                    .format(len(enc_dec_param_dict)))

        # Set up training model
        logger.info("Building model")
        training_model = Model(cost)

        # Set extensions
        logger.info("Initializing extensions")
        extensions = [
            FinishAfter(after_n_batches=config['finish_after']),
            TrainingDataMonitoring([cost], after_batch=True),
            Printing(after_batch=True),
            CheckpointNMT(config['saveto'],
                          every_n_batches=config['save_freq'])
        ]
        '''
        # Set up beam search and sampling computation graphs if necessary
        if config['hook_samples'] >= 1 or config['bleu_script'] is not None:
            logger.info("Building sampling model")
            sampling_representation = encoder.apply(
                sampling_input, tensor.ones(sampling_input.shape))
            generated = decoder.generate(
                sampling_input, sampling_representation)
            search_model = Model(generated)
            _, samples = VariableFilter(
                bricks=[decoder.sequence_generator], name="outputs")(
                    ComputationGraph(generated[1]))

        # Add sampling
        if config['hook_samples'] >= 1:
            logger.info("Building sampler")
            extensions.append(
                Sampler(model=search_model, data_stream=tr_stream,
                        hook_samples=config['hook_samples'],
                        every_n_batches=config['sampling_freq'],
                        src_vocab_size=config['src_vocab_size']))

        # Add early stopping based on bleu
        if config['bleu_script'] is not None:
            logger.info("Building bleu validator")
            extensions.append(
                BleuValidator(sampling_input, samples=samples, config=config,
                              model=search_model, data_stream=dev_stream,
                              normalize=config['normalized_bleu'],
                              every_n_batches=config['bleu_val_freq']))
        '''

        # Reload model if necessary
        if config['reload']:
            extensions.append(LoadNMT(config['saveto']))

        # Plot cost in bokeh if necessary
        if use_bokeh and BOKEH_AVAILABLE:
            extensions.append(
                Plot('Cs-En', channels=[['decoder_cost_cost']],
                     after_batch=True))

        # Set up training algorithm
        logger.info("Initializing training algorithm")
        algorithm = GradientDescent(
            cost=cost, parameters=cg.parameters,on_unused_sources='warn',
            step_rule=CompositeRule([StepClipping(config['step_clipping']),
                                     eval(config['step_rule'])()])
        )

        # Initialize main loop
        logger.info("Initializing main loop")
        main_loop = MainLoop(
            model=training_model,
            algorithm=algorithm,
            data_stream=tr_stream,
            extensions=extensions
        )

        # Train!
        main_loop.run()

    elif mode == 'translate':

        # Create Theano variables
        logger.info('Creating theano variables')
        source_sentence = tensor.lmatrix('source')
        source_topical_word=tensor.lmatrix('source_topical')

        # Get test set stream
        test_stream = get_dev_stream_with_topicalq(
            config['test_set'], config['src_vocab'],
            config['src_vocab_size'],config['topical_test_set'],config['topical_vocab'],config['topical_vocab_size'],config['unk_id'])
        ftrans = open(config['test_set'] + '.trans.out', 'w')

        # Helper utilities
        sutils = SamplingBase()
        unk_idx = config['unk_id']
        src_eos_idx = config['src_vocab_size'] - 1
        trg_eos_idx = config['trg_vocab_size'] - 1

        # Get beam search
        logger.info("Building sampling model")
        topic_embedding=topical_transformer.apply(source_topical_word);
        representation=encoder.apply(source_sentence, tensor.ones(source_sentence.shape));
        tw_representation=topical_transformer.look_up.apply(source_topical_word.T);
        content_embedding=representation[0,:,(representation.shape[2]/2):];
        generated = decoder.generate(source_sentence,representation, tw_representation,topical_embedding=topic_embedding,content_embedding=content_embedding);


        _, samples = VariableFilter(
            bricks=[decoder.sequence_generator], name="outputs")(
                ComputationGraph(generated[1]))  # generated[1] is next_outputs
        beam_search = BeamSearch(samples=samples)

        logger.info("Loading the model..")
        model = Model(generated)
        loader = LoadNMT(config['saveto'])
        loader.set_model_parameters(model, loader.load_parameters())

        # Get target vocabulary
        trg_vocab = _ensure_special_tokens(
            pickle.load(open(config['trg_vocab'], 'rb')), bos_idx=0,
            eos_idx=trg_eos_idx, unk_idx=unk_idx)
        trg_ivocab = {v: k for k, v in trg_vocab.items()}

        logger.info("Started translation: ")
        total_cost = 0.0

        for i, line in enumerate(test_stream.get_epoch_iterator()):

            seq = sutils._oov_to_unk(
                line[0], config['src_vocab_size'], unk_idx)
            seq2 = line[1];
            input_ = numpy.tile(seq, (config['beam_size'], 1))
            input_topical=numpy.tile(seq2,(config['beam_size'],1))


            # draw sample, checking to ensure we don't get an empty string back
            trans, costs = \
                beam_search.search(
                    input_values={source_sentence: input_,source_topical_word:input_topical},
                    max_length=10*len(seq), eol_symbol=src_eos_idx,
                    ignore_first_eol=True)
            '''
            # normalize costs according to the sequence lengths
            if config['normalized_bleu']:
                lengths = numpy.array([len(s) for s in trans])
                costs = costs / lengths
            '''
            #best = numpy.argsort(costs)[0]
            best=numpy.argsort(costs)[0:config['beam_size']];
            for b in best:
                try:
                    total_cost += costs[b]
                    trans_out = trans[b]

                    # convert idx to words
                    trans_out = sutils._idx_to_word(trans_out, trg_ivocab)

                except ValueError:
                    logger.info(
                        "Can NOT find a translation for line: {}".format(i+1))
                    trans_out = '<UNK>'

                print(trans_out, file=ftrans)

            if i != 0 and i % 100 == 0:
                logger.info(
                    "Translated {} lines of test set...".format(i))

        logger.info("Total cost of the test: {}".format(total_cost))
        ftrans.close()
    elif mode == 'rerank':
        # Create Theano variables
        ftrans = open(config['val_set'] + '.scores.out', 'w')
        logger.info('Creating theano variables')
        source_sentence = tensor.lmatrix('source')
        source_sentence_mask = tensor.matrix('source_mask')
        target_sentence = tensor.lmatrix('target')
        target_sentence_mask = tensor.matrix('target_mask')

        config['src_data']=config['val_set']
        config['trg_data']=config['val_set_grndtruth']
        config['batch_size']=1;
        config['sort_k_batches']=1;
        test_stream=get_tr_stream_unsorted(**config);
        logger.info("Building sampling model")
        representations= encoder.apply(
            source_sentence,  source_sentence_mask)
        costs = decoder.cost(representations, source_sentence_mask,
            target_sentence, target_sentence_mask)
        logger.info("Loading the model..")
        model = Model(costs)
        loader = LoadNMT(config['saveto'])
        loader.set_model_parameters(model, loader.load_parameters())

        costs_computer = function([source_sentence,source_sentence_mask,
                                  target_sentence,
                                  target_sentence_mask],costs)
        iterator = test_stream.get_epoch_iterator()

        scores = []
        for i, (src, src_mask, trg, trg_mask) in enumerate(iterator):
            costs = costs_computer(*[src, src_mask, trg, trg_mask])
            cost = costs.sum()
            print(i, cost)
            scores.append(cost)
            ftrans.write(str(cost)+"\n");
        ftrans.close();
Ejemplo n.º 8
0
    #        source_sentence_mask, target_sentence, target_sentence_mask)  # 定义cost 函数

    cost = decoder.cost(encoder.apply(source_sentence, tensor.ones(source_sentence.shape)),tensor.ones(source_sentence.shape), target_sentence, tensor.ones(target_sentence.shape))
    
    logger.info('Creating computational graph')
    cg = ComputationGraph(cost)  # construct the computational graph for gradient computing. it aims to optimize the model,cg包含有整个完整运算的各个权值
    # Initialize model
    logger.info('Initializing model')
    encoder.weights_init = decoder.weights_init = IsotropicGaussian(
    config['weight_scale'])
    encoder.biases_init = decoder.biases_init = Constant(0)
    encoder.push_initialization_config()  # push_initialization_config 已经被预先定义在Initializable里的方法
    decoder.push_initialization_config()
    encoder.bidir.prototype.weights_init = Orthogonal()
    decoder.transition.weights_init = Orthogonal()
    encoder.initialize()
    decoder.initialize()

    sampling_representation = encoder.apply( source_sentence, tensor.ones(source_sentence.shape))
    generated = decoder.generate(source_sentence, sampling_representation)  # modified here to add the functions.
    search_model = Model(generated)

    _, samples = VariableFilter(bricks=[decoder.sequence_generator], name="outputs")(ComputationGraph(generated[1]))

    weights = VariableFilter(bricks=[decoder.sequence_generator],name="weights")(cg.variables)
    getAlignment = function([source_sentence, target_sentence], weights)
    beam_search = BeamSearch(samples=samples)

    
    saveTo = "/Users/lqy/Documents/search_model_fr2en_backup/"
    load_model = loadNMTfromFile(saveTo)