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bettafish-company/model_pro/LSTM_model.py
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2025-04-02 20:37:28 +08:00

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Python

import torch
import torch.nn as nn
import torch.optim as optim
from torch.utils.data import Dataset, DataLoader
import numpy as np
import pandas as pd
from sklearn.model_selection import train_test_split, KFold, StratifiedKFold
from sklearn.metrics import accuracy_score, precision_score, recall_score, f1_score, confusion_matrix
from sklearn.feature_extraction.text import TfidfVectorizer
from sklearn.linear_model import LogisticRegression
import jieba
from transformers import BertTokenizer, BertModel
import logging
import os
import random
from torch.optim.lr_scheduler import ReduceLROnPlateau
from gensim.models import KeyedVectors
import json
import torch.nn.functional as F
# 配置日志记录
logging.basicConfig(level=logging.INFO, format='%(asctime)s - %(name)s - %(levelname)s - %(message)s')
logger = logging.getLogger('LSTM_model')
class TextDataset(Dataset):
"""文本数据集类,用于加载和预处理文本数据"""
def __init__(self, texts, labels, tokenizer, max_length=128):
self.texts = texts
self.labels = labels
self.tokenizer = tokenizer
self.max_length = max_length
def __len__(self):
return len(self.texts)
def __getitem__(self, idx):
text = str(self.texts[idx])
label = self.labels[idx]
# BERT分词并获得输入ID和注意力掩码
encoding = self.tokenizer.encode_plus(
text,
add_special_tokens=True,
max_length=self.max_length,
padding='max_length',
truncation=True,
return_attention_mask=True,
return_tensors='pt'
)
return {
'text': text,
'input_ids': encoding['input_ids'].flatten(),
'attention_mask': encoding['attention_mask'].flatten(),
'label': torch.tensor(label, dtype=torch.long)
}
class AttentionLayer(nn.Module):
"""注意力层"""
def __init__(self, hidden_dim):
super().__init__()
self.attention = nn.Linear(hidden_dim, 1)
def forward(self, lstm_output):
attention_weights = torch.softmax(self.attention(lstm_output), dim=1)
context_vector = torch.sum(attention_weights * lstm_output, dim=1)
return context_vector, attention_weights
# 添加数据增强类
class TextAugmenter:
def __init__(self, language='zh', synonyms_file=None):
self.language = language
self.synonyms_dict = self._load_synonyms(synonyms_file)
def _load_synonyms(self, file_path):
base_dict = {
"很好": ["非常好", "太好了", "特别好", "相当好", "真不错"],
"糟糕": ["差劲", "很差", "不好", "太差", "糟透了"],
"一般": ["还行", "凑合", "普通", "马马虎虎", "中等"],
"满意": ["很满意", "挺好", "不错", "称心如意"],
"生气": ["愤怒", "恼火", "不爽", "气愤"],
"失望": ["伤心", "难过", "不满意", "遗憾"],
# 添加更多情感词汇对
}
if file_path and os.path.exists(file_path):
try:
with open(file_path, 'r', encoding='utf-8') as f:
custom_dict = json.load(f)
base_dict.update(custom_dict)
except Exception as e:
logger.warning(f"加载同义词典失败: {e}")
return base_dict
def synonym_replacement(self, text, n=1):
words = list(jieba.cut(text))
new_words = words.copy()
num_replaced = 0
for word in list(set(words)):
if len(word) > 1 and num_replaced < n:
synonyms = self._get_synonyms(word)
if synonyms:
synonym = random.choice(synonyms)
new_words = [synonym if w == word else w for w in new_words]
num_replaced += 1
return ''.join(new_words)
def _get_synonyms(self, word):
return self.synonyms_dict.get(word, [])
def augment(self, texts, labels, augment_ratio=0.5):
augmented_texts = []
augmented_labels = []
for text, label in zip(texts, labels):
augmented_texts.append(text)
augmented_labels.append(label)
if random.random() < augment_ratio:
aug_text = self.synonym_replacement(text)
augmented_texts.append(aug_text)
augmented_labels.append(label)
return np.array(augmented_texts), np.array(augmented_labels)
class LSTMSentimentModel(nn.Module):
"""基于LSTM的情感分析模型"""
def __init__(self, vocab_size, embedding_dim, hidden_dim, output_dim, n_layers=1,
bidirectional=True, dropout=0.3, pad_idx=0, pretrained_embeddings=None):
super().__init__()
# 嵌入层
self.embedding = nn.Embedding(vocab_size, embedding_dim, padding_idx=pad_idx)
if pretrained_embeddings is not None:
self.embedding.weight.data.copy_(pretrained_embeddings)
self.embedding.weight.requires_grad = True
self.lstm = nn.LSTM(
embedding_dim,
hidden_dim,
num_layers=n_layers,
bidirectional=bidirectional,
dropout=dropout if n_layers > 1 else 0,
batch_first=True
)
# 注意力层
self.attention = AttentionLayer(hidden_dim * 2 if bidirectional else hidden_dim)
# 全连接层
fc_dim = hidden_dim * 2 if bidirectional else hidden_dim
self.fc1 = nn.Linear(fc_dim, fc_dim // 2)
self.fc2 = nn.Linear(fc_dim // 2, output_dim)
self.dropout = nn.Dropout(dropout)
self.bn = nn.BatchNorm1d(fc_dim // 2)
self.relu = nn.ReLU()
def forward(self, text, attention_mask=None):
# 文本通过嵌入层 [batch_size, seq_len] -> [batch_size, seq_len, embedding_dim]
embedded = self.embedding(text)
# 应用dropout
embedded = self.dropout(embedded)
# 通过LSTM [batch_size, seq_len, embedding_dim] -> [batch_size, seq_len, hidden_dim*2]
if attention_mask is not None:
# 创建打包的序列
lengths = attention_mask.sum(dim=1).to('cpu')
packed_embedded = nn.utils.rnn.pack_padded_sequence(
embedded, lengths, batch_first=True, enforce_sorted=False
)
packed_output, (hidden, cell) = self.lstm(packed_embedded)
# 解包序列
output, _ = nn.utils.rnn.pad_packed_sequence(packed_output, batch_first=True)
else:
output, (hidden, cell) = self.lstm(embedded)
# 应用注意力机制
context_vector, attention_weights = self.attention(output)
# 应用dropout和全连接层
x = self.dropout(context_vector)
x = self.fc1(x)
x = self.bn(x)
x = self.relu(x)
x = self.dropout(x)
x = self.fc2(x)
return x, attention_weights
# 添加早停类
class EarlyStopping:
def __init__(self, patience=5, min_delta=0):
self.patience = patience
self.min_delta = min_delta
self.counter = 0
self.best_loss = None
self.early_stop = False
def __call__(self, val_loss):
if self.best_loss is None:
self.best_loss = val_loss
elif val_loss > self.best_loss - self.min_delta:
self.counter += 1
if self.counter >= self.patience:
self.early_stop = True
else:
self.best_loss = val_loss
self.counter = 0
class LSTMModelManager:
"""LSTM模型管理类,用于训练、评估和预测"""
def __init__(self, bert_model_path, model_save_path=None, vocab_size=30522,
embedding_dim=100, hidden_dim=64, output_dim=2, n_layers=1,
bidirectional=True, dropout=0.3, word2vec_path=None, random_seed=42):
# 设置随机种子以确保可重现性
self.random_seed = random_seed
random.seed(random_seed)
np.random.seed(random_seed)
torch.manual_seed(random_seed)
if torch.cuda.is_available():
torch.cuda.manual_seed_all(random_seed)
self.device = torch.device('cuda' if torch.cuda.is_available() else 'cpu')
self.tokenizer = BertTokenizer.from_pretrained(bert_model_path)
self.vocab_size = vocab_size
self.embedding_dim = embedding_dim
self.model = LSTMSentimentModel(
vocab_size=vocab_size,
embedding_dim=embedding_dim,
hidden_dim=hidden_dim,
output_dim=output_dim,
n_layers=n_layers,
bidirectional=bidirectional,
dropout=dropout,
pad_idx=self.tokenizer.pad_token_id
).to(self.device)
self.model_save_path = model_save_path
if model_save_path and os.path.exists(model_save_path):
self.model.load_state_dict(torch.load(model_save_path, map_location=self.device))
logger.info(f"已从 {model_save_path} 加载模型")
self.augmenter = TextAugmenter()
self.early_stopping = EarlyStopping(patience=5)
# 加载预训练词向量
self.pretrained_embeddings = None
if word2vec_path and os.path.exists(word2vec_path):
try:
word_vectors = KeyedVectors.load_word2vec_format(word2vec_path, binary=True)
self.pretrained_embeddings = self._build_embedding_matrix(word_vectors)
logger.info("成功加载预训练词向量")
except Exception as e:
logger.warning(f"加载预训练词向量失败: {e}")
# 初始化对抗训练参数
self.epsilon = 0.01
self.alpha = 0.001
def _build_embedding_matrix(self, word_vectors):
embedding_matrix = torch.zeros(self.vocab_size, self.embedding_dim)
for i in range(self.vocab_size):
try:
word = self.tokenizer.convert_ids_to_tokens(i)
if word in word_vectors:
embedding_matrix[i] = torch.tensor(word_vectors[word])
except:
continue
return embedding_matrix
def adversarial_training(self, batch, criterion):
"""对抗训练步骤"""
# 计算原始损失
input_ids = batch['input_ids'].to(self.device)
attention_mask = batch['attention_mask'].to(self.device)
labels = batch['label'].to(self.device)
outputs, _ = self.model(input_ids, attention_mask)
loss = criterion(outputs, labels)
# 计算梯度
loss.backward(retain_graph=True)
# 获取嵌入层的梯度
grad_embed = self.model.embedding.weight.grad.data
# 生成对抗扰动
perturb = self.epsilon * torch.sign(grad_embed)
# 应用扰动
self.model.embedding.weight.data.add_(perturb)
# 计算对抗损失
outputs_adv, _ = self.model(input_ids, attention_mask)
loss_adv = criterion(outputs_adv, labels)
# 恢复原始嵌入
self.model.embedding.weight.data.sub_(perturb)
return loss + self.alpha * loss_adv
def train_logistic_regression(self, train_texts, train_labels, val_texts=None, val_labels=None):
"""训练逻辑回归基线模型"""
# 设置随机种子以确保可重现性
np.random.seed(self.random_seed)
vectorizer = TfidfVectorizer(max_features=5000)
X_train = vectorizer.fit_transform(train_texts)
if val_texts is None:
X_train, X_val, y_train, y_val = train_test_split(
X_train, train_labels, test_size=0.2,
stratify=train_labels,
random_state=self.random_seed # 添加随机种子
)
else:
X_val = vectorizer.transform(val_texts)
y_train, y_val = train_labels, val_labels
lr_model = LogisticRegression(
class_weight='balanced',
random_state=self.random_seed, # 添加随机种子
max_iter=1000 # 增加最大迭代次数以确保收敛
)
lr_model.fit(X_train, y_train)
val_pred = lr_model.predict(X_val)
lr_accuracy = accuracy_score(y_val, val_pred)
lr_f1 = f1_score(y_val, val_pred, average='macro')
return lr_accuracy, lr_f1
def train(self, train_texts, train_labels, val_texts=None, val_labels=None,
batch_size=16, epochs=10, learning_rate=2e-4):
"""训练模型"""
logger.info("开始训练模型...")
# 首先训练逻辑回归作为基线
lr_accuracy, lr_f1 = self.train_logistic_regression(train_texts, train_labels, val_texts, val_labels)
logger.info(f"逻辑回归基线模型 - 准确率: {lr_accuracy:.4f}, F1: {lr_f1:.4f}")
# 如果数据量小于1000,进行数据增强
if len(train_texts) < 1000:
train_texts, train_labels = self.augmenter.augment(train_texts, train_labels)
logger.info(f"数据增强后的训练集大小: {len(train_texts)}")
# 创建K折交叉验证
kf = StratifiedKFold(n_splits=5, shuffle=True, random_state=42)
fold_results = []
for fold, (train_idx, val_idx) in enumerate(kf.split(train_texts, train_labels)):
logger.info(f"训练第 {fold+1} 折...")
# 重置模型
self.model = self._create_model()
optimizer = optim.AdamW(self.model.parameters(), lr=learning_rate)
scheduler = ReduceLROnPlateau(optimizer, mode='min', patience=2)
criterion = nn.CrossEntropyLoss(weight=torch.tensor([1.0, 1.0]).to(self.device))
# 准备数据
X_train, X_val = train_texts[train_idx], train_texts[val_idx]
y_train, y_val = train_labels[train_idx], train_labels[val_idx]
train_dataset = TextDataset(X_train, y_train, self.tokenizer)
val_dataset = TextDataset(X_val, y_val, self.tokenizer)
train_loader = DataLoader(train_dataset, batch_size=batch_size, shuffle=True)
val_loader = DataLoader(val_dataset, batch_size=batch_size)
best_val_loss = float('inf')
for epoch in range(epochs):
# 训练和验证逻辑
train_loss = self._train_epoch(train_loader, optimizer, criterion)
val_loss, val_acc, val_f1 = self._validate(val_loader, criterion)
scheduler.step(val_loss)
if val_loss < best_val_loss:
best_val_loss = val_loss
if self.model_save_path:
torch.save(self.model.state_dict(),
f"{self.model_save_path}_fold{fold}.pt")
if self.early_stopping(val_loss):
break
fold_results.append({
'val_loss': val_loss,
'val_accuracy': val_acc,
'val_f1': val_f1
})
# 计算平均结果
avg_val_loss = np.mean([res['val_loss'] for res in fold_results])
avg_val_acc = np.mean([res['val_accuracy'] for res in fold_results])
avg_val_f1 = np.mean([res['val_f1'] for res in fold_results])
logger.info(f"交叉验证平均结果 - 损失: {avg_val_loss:.4f}, 准确率: {avg_val_acc:.4f}, F1: {avg_val_f1:.4f}")
# 如果LSTM模型效果比逻辑回归差,给出警告
if avg_val_acc < lr_accuracy:
logger.warning("LSTM模型性能低于逻辑回归基线,建议使用逻辑回归模型")
return avg_val_loss, avg_val_acc, avg_val_f1
def _train_epoch(self, train_loader, optimizer, criterion):
self.model.train()
total_loss = 0
for batch in train_loader:
optimizer.zero_grad()
# 使用对抗训练
loss = self.adversarial_training(batch, criterion)
loss.backward()
torch.nn.utils.clip_grad_norm_(self.model.parameters(), max_norm=1.0)
optimizer.step()
total_loss += loss.item()
return total_loss / len(train_loader)
def _validate(self, val_loader, criterion):
self.model.eval()
total_loss = 0
val_preds = []
val_labels_list = []
with torch.no_grad():
for batch in val_loader:
input_ids = batch['input_ids'].to(self.device)
attention_mask = batch['attention_mask'].to(self.device)
labels = batch['label'].to(self.device)
outputs, _ = self.model(input_ids, attention_mask)
loss = criterion(outputs, labels)
total_loss += loss.item()
_, predicted = torch.max(outputs, 1)
val_preds.extend(predicted.cpu().numpy())
val_labels_list.extend(labels.cpu().numpy())
avg_loss = total_loss / len(val_loader)
accuracy = accuracy_score(val_labels_list, val_preds)
f1 = f1_score(val_labels_list, val_preds, average='macro')
return avg_loss, accuracy, f1
def evaluate(self, test_texts, test_labels, batch_size=32):
"""评估模型"""
logger.info("评估模型...")
# 创建测试数据集和数据加载器
test_dataset = TextDataset(test_texts, test_labels, self.tokenizer)
test_dataloader = DataLoader(test_dataset, batch_size=batch_size)
# 设置为评估模式
self.model.eval()
# 损失函数
criterion = nn.CrossEntropyLoss()
test_loss = 0
test_preds = []
test_probs = []
test_labels_list = []
with torch.no_grad():
for batch in test_dataloader:
input_ids = batch['input_ids'].to(self.device)
attention_mask = batch['attention_mask'].to(self.device)
labels = batch['label'].to(self.device)
outputs, _ = self.model(input_ids, attention_mask)
loss = criterion(outputs, labels)
test_loss += loss.item()
probs = torch.softmax(outputs, dim=1)
_, predicted = torch.max(outputs, 1)
test_preds.extend(predicted.cpu().numpy())
test_probs.extend(probs.cpu().numpy())
test_labels_list.extend(labels.cpu().numpy())
# 计算平均损失
test_loss /= len(test_dataloader)
# 计算评估指标
accuracy = accuracy_score(test_labels_list, test_preds)
precision = precision_score(test_labels_list, test_preds, average='macro')
recall = recall_score(test_labels_list, test_preds, average='macro')
f1 = f1_score(test_labels_list, test_preds, average='macro')
conf_matrix = confusion_matrix(test_labels_list, test_preds)
logger.info(f'Test Loss: {test_loss:.4f}')
logger.info(f'Accuracy: {accuracy:.4f}')
logger.info(f'Precision: {precision:.4f}')
logger.info(f'Recall: {recall:.4f}')
logger.info(f'F1 Score: {f1:.4f}')
logger.info(f'Confusion Matrix:\n{conf_matrix}')
return {
'loss': test_loss,
'accuracy': accuracy,
'precision': precision,
'recall': recall,
'f1': f1,
'confusion_matrix': conf_matrix,
'predictions': test_preds,
'probabilities': test_probs
}
def predict_batch(self, texts, batch_size=32):
"""批量预测文本的情感"""
if not texts:
return None, None
# 确保文本是列表格式
if isinstance(texts, str):
texts = [texts]
# 创建数据集(没有标签,使用占位符)
dummy_labels = [0] * len(texts)
dataset = TextDataset(texts, dummy_labels, self.tokenizer)
dataloader = DataLoader(dataset, batch_size=batch_size)
# 设置为评估模式
self.model.eval()
all_preds = []
all_probs = []
with torch.no_grad():
for batch in dataloader:
input_ids = batch['input_ids'].to(self.device)
attention_mask = batch['attention_mask'].to(self.device)
outputs, _ = self.model(input_ids, attention_mask)
probs = torch.softmax(outputs, dim=1)
_, predicted = torch.max(outputs, 1)
all_preds.extend(predicted.cpu().numpy())
all_probs.extend(probs.cpu().numpy())
return all_preds, all_probs
def predict(self, text):
"""预测单个文本的情感"""
predictions, probabilities = self.predict_batch([text])
if predictions is not None and len(predictions) > 0:
return predictions[0], probabilities[0]
return None, None
# 创建全局模型实例
lstm_model_manager = LSTMModelManager(
bert_model_path='model_pro/bert_model',
model_save_path='model_pro/lstm_model.pt'
)
# 测试代码
if __name__ == "__main__":
# 加载数据
train_data = pd.read_csv('model_pro/train.csv')
dev_data = pd.read_csv('model_pro/dev.csv')
test_data = pd.read_csv('model_pro/test.csv')
# 处理数据
train_texts = train_data['text'].values
train_labels = train_data['label'].values
dev_texts = dev_data['text'].values
dev_labels = dev_data['label'].values
test_texts = test_data['text'].values
test_labels = test_data['label'].values
# 训练模型
lstm_model_manager.train(
train_texts, train_labels,
val_texts=dev_texts, val_labels=dev_labels,
batch_size=32, epochs=5
)
# 评估模型
results = lstm_model_manager.evaluate(test_texts, test_labels)
# 测试预测功能
test_sentences = [
"这件事情做得非常好",
"服务太差了,态度恶劣",
"这个产品质量一般,但价格便宜",
"我对这家公司非常满意",
]
for sentence in test_sentences:
pred, prob = lstm_model_manager.predict(sentence)
label = '良好' if pred == 0 else '不良'
confidence = prob[pred]
print(f"句子: '{sentence}' 预测结果: {label} (置信度: {confidence:.2%})")