fork from Datawhale零基础入门NLP赛事 - Task6 基于深度学习的文本分类3-BERT

BERT

微调将最后一层的第一个token即[CLS]的隐藏向量作为句子的表示，然后输入到softmax层进行分类。

预训练BERT以及相关代码下载地址：链接: https://pan.baidu.com/s/1zd6wN7elGgp1NyuzYKpvGQ 提取码: tmp5

[外链图片转存失败,源站可能有防盗链机制,建议将图片保存下来直接上传(img-mDWKY0Tw-1596553583292)(img/bert.png)]

import logging
import random

import numpy as np
import torch

logging.basicConfig(level=logging.INFO, format='%(asctime)-15s %(levelname)s: %(message)s')

# set seed
seed = 666
random.seed(seed)
np.random.seed(seed)
torch.cuda.manual_seed(seed)
torch.manual_seed(seed)

# set cuda
gpu = 0
use_cuda = gpu >= 0 and torch.cuda.is_available()
if use_cuda:
    torch.cuda.set_device(gpu)
    device = torch.device("cuda", gpu)
else:
    device = torch.device("cpu")
logging.info("Use cuda: %s, gpu id: %d.", use_cuda, gpu)

2020-07-17 12:02:34,773 INFO: Use cuda: True, gpu id: 0.

# split data to 10 fold
fold_num = 10
data_file = '../data/train_set.csv'
import pandas as pd


def all_data2fold(fold_num, num=10000):
    fold_data = []
    f = pd.read_csv(data_file, sep='\t', encoding='UTF-8')
    texts = f['text'].tolist()[:num]
    labels = f['label'].tolist()[:num]

    total = len(labels)

    index = list(range(total))
    np.random.shuffle(index)

    all_texts = []
    all_labels = []
    for i in index:
        all_texts.append(texts[i])
        all_labels.append(labels[i])

    label2id = {}
    for i in range(total):
        label = str(all_labels[i])
        if label not in label2id:
            label2id[label] = [i]
        else:
            label2id[label].append(i)

    all_index = [[] for _ in range(fold_num)]
    for label, data in label2id.items():
        # print(label, len(data))
        batch_size = int(len(data) / fold_num)
        other = len(data) - batch_size * fold_num
        for i in range(fold_num):
            cur_batch_size = batch_size + 1 if i < other else batch_size
            # print(cur_batch_size)
            batch_data = [data[i * batch_size + b] for b in range(cur_batch_size)]
            all_index[i].extend(batch_data)

    batch_size = int(total / fold_num)
    other_texts = []
    other_labels = []
    other_num = 0
    start = 0
    for fold in range(fold_num):
        num = len(all_index[fold])
        texts = [all_texts[i] for i in all_index[fold]]
        labels = [all_labels[i] for i in all_index[fold]]

        if num > batch_size:
            fold_texts = texts[:batch_size]
            other_texts.extend(texts[batch_size:])
            fold_labels = labels[:batch_size]
            other_labels.extend(labels[batch_size:])
            other_num += num - batch_size
        elif num < batch_size:
            end = start + batch_size - num
            fold_texts = texts + other_texts[start: end]
            fold_labels = labels + other_labels[start: end]
            start = end
        else:
            fold_texts = texts
            fold_labels = labels

        assert batch_size == len(fold_labels)

        # shuffle
        index = list(range(batch_size))
        np.random.shuffle(index)

        shuffle_fold_texts = []
        shuffle_fold_labels = []
        for i in index:
            shuffle_fold_texts.append(fold_texts[i])
            shuffle_fold_labels.append(fold_labels[i])

        data = {'label': shuffle_fold_labels, 'text': shuffle_fold_texts}
        fold_data.append(data)

    logging.info("Fold lens %s", str([len(data['label']) for data in fold_data]))

    return fold_data


fold_data = all_data2fold(10)

2020-07-17 12:02:39,180 INFO: Fold lens [1000, 1000, 1000, 1000, 1000, 1000, 1000, 1000, 1000, 1000]

# build train, dev, test data
fold_id = 9

# dev
dev_data = fold_data[fold_id]

# train
train_texts = []
train_labels = []
for i in range(0, fold_id):
    data = fold_data[i]
    train_texts.extend(data['text'])
    train_labels.extend(data['label'])

train_data = {'label': train_labels, 'text': train_texts}

# test
test_data_file = '../data/test_a.csv'
f = pd.read_csv(test_data_file, sep='\t', encoding='UTF-8')
texts = f['text'].tolist()
test_data = {'label': [0] * len(texts), 'text': texts}

# build vocab
from collections import Counter
from transformers import BasicTokenizer

basic_tokenizer = BasicTokenizer()


class Vocab():
    def __init__(self, train_data):
        self.min_count = 5
        self.pad = 0
        self.unk = 1
        self._id2word = ['[PAD]', '[UNK]']
        self._id2extword = ['[PAD]', '[UNK]']

        self._id2label = []
        self.target_names = []

        self.build_vocab(train_data)

        reverse = lambda x: dict(zip(x, range(len(x))))
        self._word2id = reverse(self._id2word)
        self._label2id = reverse(self._id2label)

        logging.info("Build vocab: words %d, labels %d." % (self.word_size, self.label_size))

    def build_vocab(self, data):
        self.word_counter = Counter()

        for text in data['text']:
            words = text.split()
            for word in words:
                self.word_counter[word] += 1

        for word, count in self.word_counter.most_common():
            if count >= self.min_count:
                self._id2word.append(word)

        label2name = {0: '科技', 1: '股票', 2: '体育', 3: '娱乐', 4: '时政', 5: '社会', 6: '教育', 7: '财经',
                      8: '家居', 9: '游戏', 10: '房产', 11: '时尚', 12: '彩票', 13: '星座'}

        self.label_counter = Counter(data['label'])

        for label in range(len(self.label_counter)):
            count = self.label_counter[label]
            self._id2label.append(label)
            self.target_names.append(label2name[label])

    def load_pretrained_embs(self, embfile):
        with open(embfile, encoding='utf-8') as f:
            lines = f.readlines()
            items = lines[0].split()
            word_count, embedding_dim = int(items[0]), int(items[1])

        index = len(self._id2extword)
        embeddings = np.zeros((word_count + index, embedding_dim))
        for line in lines[1:]:
            values = line.split()
            self._id2extword.append(values[0])
            vector = np.array(values[1:], dtype='float64')
            embeddings[self.unk] += vector
            embeddings[index] = vector
            index += 1

        embeddings[self.unk] = embeddings[self.unk] / word_count
        embeddings = embeddings / np.std(embeddings)

        reverse = lambda x: dict(zip(x, range(len(x))))
        self._extword2id = reverse(self._id2extword)

        assert len(set(self._id2extword)) == len(self._id2extword)

        return embeddings

    def word2id(self, xs):
        if isinstance(xs, list):
            return [self._word2id.get(x, self.unk) for x in xs]
        return self._word2id.get(xs, self.unk)

    def extword2id(self, xs):
        if isinstance(xs, list):
            return [self._extword2id.get(x, self.unk) for x in xs]
        return self._extword2id.get(xs, self.unk)

    def label2id(self, xs):
        if isinstance(xs, list):
            return [self._label2id.get(x, self.unk) for x in xs]
        return self._label2id.get(xs, self.unk)

    @property
    def word_size(self):
        return len(self._id2word)

    @property
    def extword_size(self):
        return len(self._id2extword)

    @property
    def label_size(self):
        return len(self._id2label)


vocab = Vocab(train_data)

2020-07-17 12:02:40,225 INFO: PyTorch version 1.2.0 available.

2020-07-17 12:02:43,280 INFO: Build vocab: words 4337, labels 14.

# build module
import torch.nn as nn
import torch.nn.functional as F


class Attention(nn.Module):
    def __init__(self, hidden_size):
        super(Attention, self).__init__()
        self.weight = nn.Parameter(torch.Tensor(hidden_size, hidden_size))
        self.weight.data.normal_(mean=0.0, std=0.05)

        self.bias = nn.Parameter(torch.Tensor(hidden_size))
        b = np.zeros(hidden_size, dtype=np.float32)
        self.bias.data.copy_(torch.from_numpy(b))

        self.query = nn.Parameter(torch.Tensor(hidden_size))
        self.query.data.normal_(mean=0.0, std=0.05)

    def forward(self, batch_hidden, batch_masks):
        # batch_hidden: b x len x hidden_size (2 * hidden_size of lstm)
        # batch_masks:  b x len

        # linear
        key = torch.matmul(batch_hidden, self.weight) + self.bias  # b x len x hidden

        # compute attention
        outputs = torch.matmul(key, self.query)  # b x len

        masked_outputs = outputs.masked_fill((1 - batch_masks).bool(), float(-1e32))

        attn_scores = F.softmax(masked_outputs, dim=1)  # b x len

        # 对于全零向量，-1e32的结果为 1/len, -inf为nan, 额外补0
        masked_attn_scores = attn_scores.masked_fill((1 - batch_masks).bool(), 0.0)

        # sum weighted sources
        batch_outputs = torch.bmm(masked_attn_scores.unsqueeze(1), key).squeeze(1)  # b x hidden

        return batch_outputs, attn_scores


# build word encoder
bert_path = '../emb/bert-mini/'
dropout = 0.15

from transformers import BertModel


class WordBertEncoder(nn.Module):
    def __init__(self):
        super(WordBertEncoder, self).__init__()
        self.dropout = nn.Dropout(dropout)

        self.tokenizer = WhitespaceTokenizer()
        self.bert = BertModel.from_pretrained(bert_path)

        self.pooled = False
        logging.info('Build Bert encoder with pooled {}.'.format(self.pooled))

    def encode(self, tokens):
        tokens = self.tokenizer.tokenize(tokens)
        return tokens

    def get_bert_parameters(self):
        no_decay = ['bias', 'LayerNorm.weight']
        optimizer_parameters = [
            {'params': [p for n, p in self.bert.named_parameters() if not any(nd in n for nd in no_decay)],
             'weight_decay': 0.01},
            {'params': [p for n, p in self.bert.named_parameters() if any(nd in n for nd in no_decay)],
             'weight_decay': 0.0}
        ]
        return optimizer_parameters

    def forward(self, input_ids, token_type_ids):
        # input_ids: sen_num x bert_len
        # token_type_ids: sen_num  x bert_len

        # sen_num x bert_len x 256, sen_num x 256
        sequence_output, pooled_output = self.bert(input_ids=input_ids, token_type_ids=token_type_ids)

        if self.pooled:
            reps = pooled_output
        else:
            reps = sequence_output[:, 0, :]  # sen_num x 256

        if self.training:
            reps = self.dropout(reps)

        return reps


class WhitespaceTokenizer():
    """WhitespaceTokenizer with vocab."""

    def __init__(self):
        vocab_file = bert_path + 'vocab.txt'
        self._token2id = self.load_vocab(vocab_file)
        self._id2token = {v: k for k, v in self._token2id.items()}
        self.max_len = 256
        self.unk = 1

        logging.info("Build Bert vocab with size %d." % (self.vocab_size))

    def load_vocab(self, vocab_file):
        f = open(vocab_file, 'r')
        lines = f.readlines()
        lines = list(map(lambda x: x.strip(), lines))
        vocab = dict(zip(lines, range(len(lines))))
        return vocab

    def tokenize(self, tokens):
        assert len(tokens) <= self.max_len - 2
        tokens = ["[CLS]"] + tokens + ["[SEP]"]
        output_tokens = self.token2id(tokens)
        return output_tokens

    def token2id(self, xs):
        if isinstance(xs, list):
            return [self._token2id.get(x, self.unk) for x in xs]
        return self._token2id.get(xs, self.unk)

    @property
    def vocab_size(self):
        return len(self._id2token)


# build sent encoder
sent_hidden_size = 256
sent_num_layers = 2


class SentEncoder(nn.Module):
    def __init__(self, sent_rep_size):
        super(SentEncoder, self).__init__()
        self.dropout = nn.Dropout(dropout)

        self.sent_lstm = nn.LSTM(
            input_size=sent_rep_size,
            hidden_size=sent_hidden_size,
            num_layers=sent_num_layers,
            batch_first=True,
            bidirectional=True
        )

    def forward(self, sent_reps, sent_masks):
        # sent_reps:  b x doc_len x sent_rep_size
        # sent_masks: b x doc_len

        sent_hiddens, _ = self.sent_lstm(sent_reps)  # b x doc_len x hidden*2
        sent_hiddens = sent_hiddens * sent_masks.unsqueeze(2)

        if self.training:
            sent_hiddens = self.dropout(sent_hiddens)

        return sent_hiddens

# build model
class Model(nn.Module):
    def __init__(self, vocab):
        super(Model, self).__init__()
        self.sent_rep_size = 256
        self.doc_rep_size = sent_hidden_size * 2
        self.all_parameters = {}
        parameters = []
        self.word_encoder = WordBertEncoder()
        bert_parameters = self.word_encoder.get_bert_parameters()

        self.sent_encoder = SentEncoder(self.sent_rep_size)
        self.sent_attention = Attention(self.doc_rep_size)
        parameters.extend(list(filter(lambda p: p.requires_grad, self.sent_encoder.parameters())))
        parameters.extend(list(filter(lambda p: p.requires_grad, self.sent_attention.parameters())))

        self.out = nn.Linear(self.doc_rep_size, vocab.label_size, bias=True)
        parameters.extend(list(filter(lambda p: p.requires_grad, self.out.parameters())))

        if use_cuda:
            self.to(device)

        if len(parameters) > 0:
            self.all_parameters["basic_parameters"] = parameters
        self.all_parameters["bert_parameters"] = bert_parameters

        logging.info('Build model with bert word encoder, lstm sent encoder.')

        para_num = sum([np.prod(list(p.size())) for p in self.parameters()])
        logging.info('Model param num: %.2f M.' % (para_num / 1e6))

    def forward(self, batch_inputs):
        # batch_inputs(batch_inputs1, batch_inputs2): b x doc_len x sent_len
        # batch_masks : b x doc_len x sent_len
        batch_inputs1, batch_inputs2, batch_masks = batch_inputs
        batch_size, max_doc_len, max_sent_len = batch_inputs1.shape[0], batch_inputs1.shape[1], batch_inputs1.shape[2]
        batch_inputs1 = batch_inputs1.view(batch_size * max_doc_len, max_sent_len)  # sen_num x sent_len
        batch_inputs2 = batch_inputs2.view(batch_size * max_doc_len, max_sent_len)  # sen_num x sent_len
        batch_masks = batch_masks.view(batch_size * max_doc_len, max_sent_len)  # sen_num x sent_len

        sent_reps = self.word_encoder(batch_inputs1, batch_inputs2)  # sen_num x sent_rep_size

        sent_reps = sent_reps.view(batch_size, max_doc_len, self.sent_rep_size)  # b x doc_len x sent_rep_size
        batch_masks = batch_masks.view(batch_size, max_doc_len, max_sent_len)  # b x doc_len x max_sent_len
        sent_masks = batch_masks.bool().any(2).float()  # b x doc_len

        sent_hiddens = self.sent_encoder(sent_reps, sent_masks)  # b x doc_len x doc_rep_size
        doc_reps, atten_scores = self.sent_attention(sent_hiddens, sent_masks)  # b x doc_rep_size

        batch_outputs = self.out(doc_reps)  # b x num_labels

        return batch_outputs
    
model = Model(vocab)

2020-07-17 12:02:43,364 INFO: Build Bert vocab with size 5981.

2020-07-17 12:02:43,365 INFO: loading configuration file ../emb/bert-mini/config.json

2020-07-17 12:02:43,365 INFO: Model config BertConfig {

  "attention_probs_dropout_prob": 0.1,

  "hidden_act": "gelu",

  "hidden_dropout_prob": 0.1,

  "hidden_size": 256,

  "initializer_range": 0.02,

  "intermediate_size": 1024,

  "layer_norm_eps": 1e-12,

  "max_position_embeddings": 256,

  "model_type": "bert",

  "num_attention_heads": 4,

  "num_hidden_layers": 4,

  "pad_token_id": 0,

  "type_vocab_size": 2,

  "vocab_size": 5981

}



2020-07-17 12:02:43,366 INFO: loading weights file ../emb/bert-mini/pytorch_model.bin

2020-07-17 12:02:43,439 INFO: Build Bert encoder with pooled False.

2020-07-17 12:02:45,040 INFO: Build model with bert word encoder, lstm sent encoder.

2020-07-17 12:02:45,041 INFO: Model param num: 7.72 M.

# build optimizer
learning_rate = 2e-4
bert_lr = 5e-5
decay = .75
decay_step = 1000
from transformers import AdamW, get_linear_schedule_with_warmup


class Optimizer:
    def __init__(self, model_parameters, steps):
        self.all_params = []
        self.optims = []
        self.schedulers = []

        for name, parameters in model_parameters.items():
            if name.startswith("basic"):
                optim = torch.optim.Adam(parameters, lr=learning_rate)
                self.optims.append(optim)

                l = lambda step: decay ** (step // decay_step)
                scheduler = torch.optim.lr_scheduler.LambdaLR(optim, lr_lambda=l)
                self.schedulers.append(scheduler)
                self.all_params.extend(parameters)
            elif name.startswith("bert"):
                optim_bert = AdamW(parameters, bert_lr, eps=1e-8)
                self.optims.append(optim_bert)

                scheduler_bert = get_linear_schedule_with_warmup(optim_bert, 0, steps)
                self.schedulers.append(scheduler_bert)

                for group in parameters:
                    for p in group['params']:
                        self.all_params.append(p)
            else:
                Exception("no nameed parameters.")

        self.num = len(self.optims)

    def step(self):
        for optim, scheduler in zip(self.optims, self.schedulers):
            optim.step()
            scheduler.step()
            optim.zero_grad()

    def zero_grad(self):
        for optim in self.optims:
            optim.zero_grad()

    def get_lr(self):
        lrs = tuple(map(lambda x: x.get_lr()[-1], self.schedulers))
        lr = ' %.5f' * self.num
        res = lr % lrs
        return res

# build dataset
def sentence_split(text, vocab, max_sent_len=256, max_segment=16):
    words = text.strip().split()
    document_len = len(words)

    index = list(range(0, document_len, max_sent_len))
    index.append(document_len)

    segments = []
    for i in range(len(index) - 1):
        segment = words[index[i]: index[i + 1]]
        assert len(segment) > 0
        segment = [word if word in vocab._id2word else '<UNK>' for word in segment]
        segments.append([len(segment), segment])

    assert len(segments) > 0
    if len(segments) > max_segment:
        segment_ = int(max_segment / 2)
        return segments[:segment_] + segments[-segment_:]
    else:
        return segments


def get_examples(data, word_encoder, vocab, max_sent_len=256, max_segment=8):
    label2id = vocab.label2id
    examples = []

    for text, label in zip(data['text'], data['label']):
        # label
        id = label2id(label)

        # words
        sents_words = sentence_split(text, vocab, max_sent_len-2, max_segment)
        doc = []
        for sent_len, sent_words in sents_words:
            token_ids = word_encoder.encode(sent_words)
            sent_len = len(token_ids)
            token_type_ids = [0] * sent_len
            doc.append([sent_len, token_ids, token_type_ids])
        examples.append([id, len(doc), doc])

    logging.info('Total %d docs.' % len(examples))
    return examples

# build loader

def batch_slice(data, batch_size):
    batch_num = int(np.ceil(len(data) / float(batch_size)))
    for i in range(batch_num):
        cur_batch_size = batch_size if i < batch_num - 1 else len(data) - batch_size * i
        docs = [data[i * batch_size + b] for b in range(cur_batch_size)]

        yield docs


def data_iter(data, batch_size, shuffle=True, noise=1.0):
    """
    randomly permute data, then sort by source length, and partition into batches
    ensure that the length of  sentences in each batch
    """

    batched_data = []
    if shuffle:
        np.random.shuffle(data)

    lengths = [example[1] for example in data]
    noisy_lengths = [- (l + np.random.uniform(- noise, noise)) for l in lengths]
    sorted_indices = np.argsort(noisy_lengths).tolist()
    sorted_data = [data[i] for i in sorted_indices]

    batched_data.extend(list(batch_slice(sorted_data, batch_size)))

    if shuffle:
        np.random.shuffle(batched_data)

    for batch in batched_data:
        yield batch

# some function
from sklearn.metrics import f1_score, precision_score, recall_score


def get_score(y_ture, y_pred):
    y_ture = np.array(y_ture)
    y_pred = np.array(y_pred)
    f1 = f1_score(y_ture, y_pred, average='macro') * 100
    p = precision_score(y_ture, y_pred, average='macro') * 100
    r = recall_score(y_ture, y_pred, average='macro') * 100

    return str((reformat(p, 2), reformat(r, 2), reformat(f1, 2))), reformat(f1, 2)


def reformat(num, n):
    return float(format(num, '0.' + str(n) + 'f'))

# build trainer

import time
from sklearn.metrics import classification_report

clip = 5.0
epochs = 1
early_stops = 3
log_interval = 50

test_batch_size = 16
train_batch_size = 16

save_model = './bert.bin'
save_test = './bert.csv'

class Trainer():
    def __init__(self, model, vocab):
        self.model = model
        self.report = True
        
        self.train_data = get_examples(train_data, model.word_encoder, vocab)
        self.batch_num = int(np.ceil(len(self.train_data) / float(train_batch_size)))
        self.dev_data = get_examples(dev_data, model.word_encoder, vocab)
        self.test_data = get_examples(test_data, model.word_encoder, vocab)

        # criterion
        self.criterion = nn.CrossEntropyLoss()

        # label name
        self.target_names = vocab.target_names

        # optimizer
        self.optimizer = Optimizer(model.all_parameters, steps=self.batch_num * epochs)

        # count
        self.step = 0
        self.early_stop = -1
        self.best_train_f1, self.best_dev_f1 = 0, 0
        self.last_epoch = epochs

    def train(self):
        logging.info('Start training...')
        for epoch in range(1, epochs + 1):
            train_f1 = self._train(epoch)

            dev_f1 = self._eval(epoch)

            if self.best_dev_f1 <= dev_f1:
                logging.info(
                    "Exceed history dev = %.2f, current dev = %.2f" % (self.best_dev_f1, dev_f1))
                torch.save(self.model.state_dict(), save_model)

                self.best_train_f1 = train_f1
                self.best_dev_f1 = dev_f1
                self.early_stop = 0
            else:
                self.early_stop += 1
                if self.early_stop == early_stops:
                    logging.info(
                        "Eearly stop in epoch %d, best train: %.2f, dev: %.2f" % (
                            epoch - early_stops, self.best_train_f1, self.best_dev_f1))
                    self.last_epoch = epoch
                    break
    def test(self):
        self.model.load_state_dict(torch.load(save_model))
        self._eval(self.last_epoch + 1, test=True)

    def _train(self, epoch):
        self.optimizer.zero_grad()
        self.model.train()

        start_time = time.time()
        epoch_start_time = time.time()
        overall_losses = 0
        losses = 0
        batch_idx = 1
        y_pred = []
        y_true = []
        for batch_data in data_iter(self.train_data, train_batch_size, shuffle=True):
            torch.cuda.empty_cache()
            batch_inputs, batch_labels = self.batch2tensor(batch_data)
            batch_outputs = self.model(batch_inputs)
            loss = self.criterion(batch_outputs, batch_labels)
            loss.backward()

            loss_value = loss.detach().cpu().item()
            losses += loss_value
            overall_losses += loss_value

            y_pred.extend(torch.max(batch_outputs, dim=1)[1].cpu().numpy().tolist())
            y_true.extend(batch_labels.cpu().numpy().tolist())

            nn.utils.clip_grad_norm_(self.optimizer.all_params, max_norm=clip)
            for optimizer, scheduler in zip(self.optimizer.optims, self.optimizer.schedulers):
                optimizer.step()
                scheduler.step()
            self.optimizer.zero_grad()

            self.step += 1

            if batch_idx % log_interval == 0:
                elapsed = time.time() - start_time

                lrs = self.optimizer.get_lr()
                logging.info(
                    '| epoch {:3d} | step {:3d} | batch {:3d}/{:3d} | lr{} | loss {:.4f} | s/batch {:.2f}'.format(
                        epoch, self.step, batch_idx, self.batch_num, lrs,
                        losses / log_interval,
                        elapsed / log_interval))

                losses = 0
                start_time = time.time()

            batch_idx += 1

        overall_losses /= self.batch_num
        during_time = time.time() - epoch_start_time

        # reformat
        overall_losses = reformat(overall_losses, 4)
        score, f1 = get_score(y_true, y_pred)

        logging.info(
            '| epoch {:3d} | score {} | f1 {} | loss {:.4f} | time {:.2f}'.format(epoch, score, f1,
                                                                                  overall_losses,
                                                                                  during_time))
        if set(y_true) == set(y_pred) and self.report:
            report = classification_report(y_true, y_pred, digits=4, target_names=self.target_names)
            logging.info('\n' + report)

        return f1

    def _eval(self, epoch, test=False):
        self.model.eval()
        start_time = time.time()

        y_pred = []
        y_true = []
        with torch.no_grad():
            for batch_data in data_iter(self.dev_data, test_batch_size, shuffle=False):
                torch.cuda.empty_cache()
                batch_inputs, batch_labels = self.batch2tensor(batch_data)
                batch_outputs = self.model(batch_inputs)
                y_pred.extend(torch.max(batch_outputs, dim=1)[1].cpu().numpy().tolist())
                y_true.extend(batch_labels.cpu().numpy().tolist())

            score, f1 = get_score(y_true, y_pred)

            during_time = time.time() - start_time
            
            if test:
                df = pd.DataFrame({'label': y_pred})
                df.to_csv(save_test, index=False, sep=',')
            else:
                logging.info(
                    '| epoch {:3d} | dev | score {} | f1 {} | time {:.2f}'.format(epoch, score, f1,
                                                                              during_time))
                if set(y_true) == set(y_pred) and self.report:
                    report = classification_report(y_true, y_pred, digits=4, target_names=self.target_names)
                    logging.info('\n' + report)

        return f1

    def batch2tensor(self, batch_data):
        '''
            [[label, doc_len, [[sent_len, [sent_id0, ...], [sent_id1, ...]], ...]]
        '''
        batch_size = len(batch_data)
        doc_labels = []
        doc_lens = []
        doc_max_sent_len = []
        for doc_data in batch_data:
            doc_labels.append(doc_data[0])
            doc_lens.append(doc_data[1])
            sent_lens = [sent_data[0] for sent_data in doc_data[2]]
            max_sent_len = max(sent_lens)
            doc_max_sent_len.append(max_sent_len)

        max_doc_len = max(doc_lens)
        max_sent_len = max(doc_max_sent_len)

        batch_inputs1 = torch.zeros((batch_size, max_doc_len, max_sent_len), dtype=torch.int64)
        batch_inputs2 = torch.zeros((batch_size, max_doc_len, max_sent_len), dtype=torch.int64)
        batch_masks = torch.zeros((batch_size, max_doc_len, max_sent_len), dtype=torch.float32)
        batch_labels = torch.LongTensor(doc_labels)

        for b in range(batch_size):
            for sent_idx in range(doc_lens[b]):
                sent_data = batch_data[b][2][sent_idx]
                for word_idx in range(sent_data[0]):
                    batch_inputs1[b, sent_idx, word_idx] = sent_data[1][word_idx]
                    batch_inputs2[b, sent_idx, word_idx] = sent_data[2][word_idx]
                    batch_masks[b, sent_idx, word_idx] = 1

        if use_cuda:
            batch_inputs1 = batch_inputs1.to(device)
            batch_inputs2 = batch_inputs2.to(device)
            batch_masks = batch_masks.to(device)
            batch_labels = batch_labels.to(device)

        return (batch_inputs1, batch_inputs2, batch_masks), batch_labels

# train
trainer = Trainer(model, vocab)
trainer.train()

2020-07-17 12:03:16,802 INFO: Total 9000 docs.

2020-07-17 12:03:20,218 INFO: Total 1000 docs.

2020-07-17 12:06:19,245 INFO: Total 50000 docs.

2020-07-17 12:06:19,245 INFO: Start training...

2020-07-17 12:06:38,493 INFO: | epoch   1 | step  50 | batch  50/563 | lr 0.00020 0.00005 | loss 2.0764 | s/batch 0.38

2020-07-17 12:06:57,096 INFO: | epoch   1 | step 100 | batch 100/563 | lr 0.00020 0.00004 | loss 1.2976 | s/batch 0.37

2020-07-17 12:07:14,320 INFO: | epoch   1 | step 150 | batch 150/563 | lr 0.00020 0.00004 | loss 0.8577 | s/batch 0.34

2020-07-17 12:07:30,075 INFO: | epoch   1 | step 200 | batch 200/563 | lr 0.00020 0.00003 | loss 0.7951 | s/batch 0.32

2020-07-17 12:07:48,252 INFO: | epoch   1 | step 250 | batch 250/563 | lr 0.00020 0.00003 | loss 0.7110 | s/batch 0.36

2020-07-17 12:08:05,002 INFO: | epoch   1 | step 300 | batch 300/563 | lr 0.00020 0.00002 | loss 0.7157 | s/batch 0.33

2020-07-17 12:08:23,702 INFO: | epoch   1 | step 350 | batch 350/563 | lr 0.00020 0.00002 | loss 0.4552 | s/batch 0.37

2020-07-17 12:08:42,488 INFO: | epoch   1 | step 400 | batch 400/563 | lr 0.00020 0.00001 | loss 0.6583 | s/batch 0.38

2020-07-17 12:08:59,988 INFO: | epoch   1 | step 450 | batch 450/563 | lr 0.00020 0.00001 | loss 0.4896 | s/batch 0.35

2020-07-17 12:09:16,801 INFO: | epoch   1 | step 500 | batch 500/563 | lr 0.00020 0.00001 | loss 0.4260 | s/batch 0.34

2020-07-17 12:09:35,899 INFO: | epoch   1 | step 550 | batch 550/563 | lr 0.00020 0.00000 | loss 0.4927 | s/batch 0.38

2020-07-17 12:09:39,842 INFO: | epoch   1 | score (70.87, 58.89, 62.61) | f1 62.61 | loss 0.8048 | time 200.59

2020-07-17 12:09:39,858 INFO: 

              precision    recall  f1-score   support



          科技     0.7656    0.8179    0.7909      1697

          股票     0.7021    0.8923    0.7858      1680

          体育     0.8852    0.9224    0.9035      1405

          娱乐     0.7780    0.8157    0.7964       971

          时政     0.7809    0.7028    0.7398       710

          社会     0.6862    0.7133    0.6995       558

          教育     0.8396    0.7363    0.7845       455

          财经     0.7212    0.3099    0.4335       384

          家居     0.6667    0.6043    0.6339       374

          游戏     0.7772    0.5125    0.6177       279

          房产     0.7063    0.4633    0.5596       218

          时尚     0.6747    0.3784    0.4848       148

          彩票     0.9375    0.3750    0.5357        80

          星座     0.0000    0.0000    0.0000        41



    accuracy                         0.7647      9000

   macro avg     0.7087    0.5889    0.6261      9000

weighted avg     0.7632    0.7647    0.7544      9000



/home/dell/miniconda3/envs/py36/lib/python3.6/site-packages/sklearn/metrics/_classification.py:1268: UndefinedMetricWarning: Precision is ill-defined and being set to 0.0 in labels with no predicted samples. Use `zero_division` parameter to control this behavior.

  _warn_prf(average, modifier, msg_start, len(result))

2020-07-17 12:09:55,088 INFO: | epoch   1 | dev | score (77.78, 73.19, 74.56) | f1 74.56 | time 15.23

2020-07-17 12:09:55,089 INFO: Exceed history dev = 0.00, current dev = 74.56

# test
trainer.test()

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