示例#1
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def validate_unofficial(args, data_loader, model, global_stats, mode):
    """Run one full unofficial validation.
    Unofficial = doesn't use SQuAD script.
    """
    eval_time = utils.Timer()
    start_acc = utils.AverageMeter()
    end_acc = utils.AverageMeter()
    exact_match = utils.AverageMeter()

    # Make predictions
    examples = 0
    for ex in data_loader:
        batch_size = ex[0].size(0)
        pred_s, pred_e, _ = model.predict(ex)
        target_s, target_e = ex[-3:-1]

        # We get metrics for independent start/end and joint start/end
        accuracies = eval_accuracies(pred_s, target_s, pred_e, target_e)
        start_acc.update(accuracies[0], batch_size)
        end_acc.update(accuracies[1], batch_size)
        exact_match.update(accuracies[2], batch_size)

        # If getting train accuracies, sample max 10k
        examples += batch_size
        if mode == 'train' and examples >= 1e4:
            break

    logger.info('%s valid unofficial: Epoch = %d | start = %.2f | ' %
                (mode, global_stats['epoch'], start_acc.avg) +
                'end = %.2f | exact = %.2f | examples = %d | ' %
                (end_acc.avg, exact_match.avg, examples) +
                'valid time = %.2f (s)' % eval_time.time())

    return {'exact_match': exact_match.avg}
示例#2
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def validate_official(args, data_loader, model, global_stats, offsets, texts,
                      answers):
    """Run one full official validation. Uses exact spans and same
    exact match/F1 score computation as in the SQuAD script.

    Extra arguments:
        offsets: The character start/end indices for the tokens in each context.
        texts: Map of qid --> raw text of examples context (matches offsets).
        answers: Map of qid --> list of accepted answers.
    """
    eval_time = utils.Timer()
    f1 = utils.AverageMeter()
    exact_match = utils.AverageMeter()

    # Run through examples
    examples = 0
    for ex in data_loader:
        ex_id, batch_size = ex[-1], ex[0].size(0)
        pred_s, pred_e, _ = model.predict(ex)

        for i in range(batch_size):
            s_offset = offsets[ex_id[i]][pred_s[i][0]][0]
            e_offset = offsets[ex_id[i]][pred_e[i][0]][1]
            prediction = texts[ex_id[i]][s_offset:e_offset]

            # Compute metrics
            ground_truths = answers[ex_id[i]]
            exact_match.update(
                utils.metric_max_over_ground_truths(utils.exact_match_score,
                                                    prediction, ground_truths))
            f1.update(
                utils.metric_max_over_ground_truths(utils.f1_score, prediction,
                                                    ground_truths))

        examples += batch_size

    logger.info('dev valid official: Epoch = %d | EM = %.2f | ' %
                (global_stats['epoch'], exact_match.avg * 100) +
                'F1 = %.2f | examples = %d | valid time = %.2f (s)' %
                (f1.avg * 100, examples, eval_time.time()))

    return {'exact_match': exact_match.avg * 100, 'f1': f1.avg * 100}
示例#3
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def train(args, data_loader, model, global_stats):
    """Run through one epoch of model training with the provided data loader."""
    # Initialize meters + timers
    train_loss = utils.AverageMeter()
    epoch_time = utils.Timer()

    # Run one epoch
    for idx, ex in enumerate(data_loader):
        train_loss.update(*model.update(ex))
        if idx % args.display_iter == 0:
            logger.info('train: Epoch = %d | iter = %d/%d | ' %
                        (global_stats['epoch'], idx, len(data_loader)) +
                        'loss = %.2f | elapsed time = %.2f (s)' %
                        (train_loss.avg, global_stats['timer'].time()))
            train_loss.reset()

    logger.info('train: Epoch %d done. Time for epoch = %.2f (s)' %
                (global_stats['epoch'], epoch_time.time()))

    # Checkpoint
    if args.checkpoint:
        model.checkpoint(args.model_file + '.checkpoint',
                         global_stats['epoch'] + 1)
示例#4
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def main(args):
    # --------------------------------------------------------------------------
    # DATA
    logger.info('-' * 100)
    logger.info('Load data files')
    train_exs = utils.load_data(args, args.train_file, skip_no_answer=True)
    logger.info('Num train examples = %d' % len(train_exs))
    dev_exs = utils.load_data(args, args.dev_file)
    logger.info('Num dev examples = %d' % len(dev_exs))

    # If we are doing offician evals then we need to:
    # 1) Load the original text to retrieve spans from offsets.
    # 2) Load the (multiple) text answers for each question.
    if args.official_eval:
        dev_texts = utils.load_text(args.dev_json)
        dev_offsets = {ex['id']: ex['offsets'] for ex in dev_exs}
        dev_answers = utils.load_answers(args.dev_json)

    # --------------------------------------------------------------------------
    # MODEL
    logger.info('-' * 100)
    start_epoch = 0
    if args.checkpoint and os.path.isfile(args.model_file + '.checkpoint'):
        # Just resume training, no modifications.
        logger.info('Found a checkpoint...')
        checkpoint_file = args.model_file + '.checkpoint'
        model, start_epoch = DocReader.load_checkpoint(checkpoint_file, args)
    else:
        # Training starts fresh. But the model state is either pretrained or
        # newly (randomly) initialized.
        if args.pretrained:
            logger.info('Using pretrained model...')
            model = DocReader.load(args.pretrained, args)
            if args.expand_dictionary:
                logger.info('Expanding dictionary for new data...')
                # Add words in training + dev examples
                words = utils.load_words(args, train_exs + dev_exs)
                added = model.expand_dictionary(words)
                # Load pretrained embeddings for added words
                if args.embedding_file:
                    model.load_embeddings(added, args.embedding_file)

        else:
            logger.info('Training model from scratch...')
            model = init_from_scratch(args, train_exs, dev_exs)

        # Set up partial tuning of embeddings
        if args.tune_partial > 0:
            logger.info('-' * 100)
            logger.info('Counting %d most frequent question words' %
                        args.tune_partial)
            top_words = utils.top_question_words(args, train_exs,
                                                 model.word_dict)
            for word in top_words[:5]:
                logger.info(word)
            logger.info('...')
            for word in top_words[-6:-1]:
                logger.info(word)
            model.tune_embeddings([w[0] for w in top_words])

        # Set up optimizer
        model.init_optimizer()

    # Use the GPU?
    if args.cuda:
        model.cuda()

    # Use multiple GPUs?
    if args.parallel:
        model.parallelize()

    # --------------------------------------------------------------------------
    # DATA ITERATORS
    # Two datasets: train and dev. If we sort by length it's faster.
    logger.info('-' * 100)
    logger.info('Make data loaders')
    train_dataset = data.ReaderDataset(train_exs, model, single_answer=True)
    if args.sort_by_len:
        train_sampler = data.SortedBatchSampler(train_dataset.lengths(),
                                                args.batch_size,
                                                shuffle=True)
    else:
        train_sampler = torch.utils.data.sampler.RandomSampler(train_dataset)
    train_loader = torch.utils.data.DataLoader(
        train_dataset,
        batch_size=args.batch_size,
        sampler=train_sampler,
        num_workers=args.data_workers,
        collate_fn=vector.batchify,
        pin_memory=args.cuda,
    )
    dev_dataset = data.ReaderDataset(dev_exs, model, single_answer=False)
    if args.sort_by_len:
        dev_sampler = data.SortedBatchSampler(dev_dataset.lengths(),
                                              args.test_batch_size,
                                              shuffle=False)
    else:
        dev_sampler = torch.utils.data.sampler.SequentialSampler(dev_dataset)
    dev_loader = torch.utils.data.DataLoader(
        dev_dataset,
        batch_size=args.test_batch_size,
        sampler=dev_sampler,
        num_workers=args.data_workers,
        collate_fn=vector.batchify,
        pin_memory=args.cuda,
    )

    # -------------------------------------------------------------------------
    # PRINT CONFIG
    logger.info('-' * 100)
    logger.info('CONFIG:\n%s' %
                json.dumps(vars(args), indent=4, sort_keys=True))

    # --------------------------------------------------------------------------
    # TRAIN/VALID LOOP
    logger.info('-' * 100)
    logger.info('Starting training...')
    stats = {'timer': utils.Timer(), 'epoch': 0, 'best_valid': 0}
    for epoch in range(start_epoch, args.num_epochs):
        stats['epoch'] = epoch

        # Train
        train(args, train_loader, model, stats)

        # Validate unofficial (train)
        validate_unofficial(args, train_loader, model, stats, mode='train')

        # Validate unofficial (dev)
        result = validate_unofficial(args,
                                     dev_loader,
                                     model,
                                     stats,
                                     mode='dev')

        # Validate official
        if args.official_eval:
            result = validate_official(args, dev_loader, model, stats,
                                       dev_offsets, dev_texts, dev_answers)

        # Save best valid
        if result[args.valid_metric] > stats['best_valid']:
            logger.info('Best valid: %s = %.2f (epoch %d, %d updates)' %
                        (args.valid_metric, result[args.valid_metric],
                         stats['epoch'], model.updates))
            model.save(args.model_file)
            stats['best_valid'] = result[args.valid_metric]