请给出多id,多标签时序二分类问题的代码
时间: 2023-10-15 12:08:07 浏览: 86
基于python实现的心电时序多标签分类源码+数据集+操作说明.zip
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下面是一个基于Pytorch的多id、多标签时序二分类问题的代码示例:
```python
import torch
import torch.nn as nn
import torch.optim as optim
from torch.utils.data import Dataset, DataLoader
class MultiLabelDataset(Dataset):
def __init__(self, data, max_seq_length):
self.data = data
self.max_seq_length = max_seq_length
def __len__(self):
return len(self.data)
def __getitem__(self, idx):
# 获取文本和标签
text = self.data[idx]['text']
labels = self.data[idx]['labels']
# 将文本转换为词向量,并根据max_seq_length填充或截断
text_vector = []
for word in text.split():
if word in word2vec:
text_vector.append(word2vec[word])
else:
text_vector.append(word2vec['unk'])
if len(text_vector) < self.max_seq_length:
text_vector += [word2vec['pad']] * (self.max_seq_length - len(text_vector))
else:
text_vector = text_vector[:self.max_seq_length]
# 将标签转换为多标签二进制形式
label_vector = []
for label in labels:
label_vector.append(int(label in label_set))
return torch.tensor(text_vector), torch.tensor(label_vector)
class MultiLabelLSTM(nn.Module):
def __init__(self, input_size, hidden_size, output_size):
super(MultiLabelLSTM, self).__init__()
self.input_size = input_size
self.hidden_size = hidden_size
self.output_size = output_size
self.lstm = nn.LSTM(input_size, hidden_size)
self.fc = nn.Linear(hidden_size, output_size)
def forward(self, x):
lstm_out, _ = self.lstm(x.view(len(x), 1, -1))
out = self.fc(lstm_out.view(len(x), -1))
return out
# 定义超参数
max_seq_length = 100
input_size = 300
hidden_size = 128
output_size = len(label_set)
# 加载词向量和数据
word2vec = load_word2vec('word2vec.bin')
train_data = load_train_data('train_data.json')
valid_data = load_valid_data('valid_data.json')
# 定义数据集和数据加载器
train_dataset = MultiLabelDataset(train_data, max_seq_length)
valid_dataset = MultiLabelDataset(valid_data, max_seq_length)
train_loader = DataLoader(train_dataset, batch_size=32, shuffle=True)
valid_loader = DataLoader(valid_dataset, batch_size=32, shuffle=False)
# 定义模型和优化器
model = MultiLabelLSTM(input_size, hidden_size, output_size)
optimizer = optim.Adam(model.parameters(), lr=0.001)
# 训练模型
for epoch in range(10):
train_loss = 0
valid_loss = 0
train_acc = 0
valid_acc = 0
# 训练模式
model.train()
for batch_text, batch_label in train_loader:
optimizer.zero_grad()
batch_text = batch_text.float().to(device)
batch_label = batch_label.float().to(device)
output = model(batch_text)
loss = nn.BCEWithLogitsLoss()(output, batch_label)
loss.backward()
optimizer.step()
train_loss += loss.item()
train_acc += ((torch.sigmoid(output) > 0.5).int() == batch_label.int()).all(dim=1).float().mean().item()
train_loss /= len(train_loader)
train_acc /= len(train_loader)
# 验证模式
model.eval()
with torch.no_grad():
for batch_text, batch_label in valid_loader:
batch_text = batch_text.float().to(device)
batch_label = batch_label.float().to(device)
output = model(batch_text)
loss = nn.BCEWithLogitsLoss()(output, batch_label)
valid_loss += loss.item()
valid_acc += ((torch.sigmoid(output) > 0.5).int() == batch_label.int()).all(dim=1).float().mean().item()
valid_loss /= len(valid_loader)
valid_acc /= len(valid_loader)
print('Epoch: {} Train Loss: {:.3f} Train Acc: {:.3f} Valid Loss: {:.3f} Valid Acc: {:.3f}'.format(
epoch+1, train_loss, train_acc, valid_loss, valid_acc))
```
其中,`MultiLabelDataset`类用于加载数据集,`MultiLabelLSTM`类用于定义模型,`train_loader`和`valid_loader`用于加载训练集和验证集。在训练模型时,我们使用`nn.BCEWithLogitsLoss()`作为损失函数,输出层不需要使用sigmoid激活函数,因为`nn.BCEWithLogitsLoss()`已经对输出进行了sigmoid处理。我们还计算了训练集和验证集的准确率,以便监控模型的性能。
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