4哥特征的csv文件利用transformer模型进行5分类的python代码
时间: 2024-04-15 07:26:35 浏览: 158
python实现对csv文件的读取和对第5列的排序
要使用Transformer模型进行5分类,你可以使用Hugging Face的`transformers`库中提供的预训练模型和工具。下面是一个示例代码:
```python
import pandas as pd
import torch
from sklearn.model_selection import train_test_split
from transformers import BertTokenizer, BertForSequenceClassification, AdamW
# 读取CSV文件
data = pd.read_csv('data.csv')
# 提取特征列和标签列
features = data['特征列'] # 替换为实际的特征列名
labels = data['标签列'] # 替换为实际的标签列名
# 划分训练集和测试集
train_features, test_features, train_labels, test_labels = train_test_split(features, labels, test_size=0.2)
# 初始化BertTokenizer和BertForSequenceClassification模型
tokenizer = BertTokenizer.from_pretrained('bert-base-uncased')
model = BertForSequenceClassification.from_pretrained('bert-base-uncased', num_labels=5) # 5分类,根据实际情况调整
# 编码输入数据
train_encodings = tokenizer(train_features.tolist(), truncation=True, padding=True)
test_encodings = tokenizer(test_features.tolist(), truncation=True, padding=True)
# 转换数据为PyTorch张量
train_dataset = torch.utils.data.TensorDataset(torch.tensor(train_encodings['input_ids']),
torch.tensor(train_encodings['attention_mask']),
torch.tensor(train_labels.tolist()))
test_dataset = torch.utils.data.TensorDataset(torch.tensor(test_encodings['input_ids']),
torch.tensor(test_encodings['attention_mask']),
torch.tensor(test_labels.tolist()))
# 定义训练参数
train_params = {'batch_size': 16,
'shuffle': True}
# 初始化优化器和学习率调度器
optimizer = AdamW(model.parameters(), lr=1e-5)
scheduler = torch.optim.lr_scheduler.StepLR(optimizer, step_size=5, gamma=0.1)
# 训练模型
train_dataloader = torch.utils.data.DataLoader(train_dataset, **train_params)
model.train()
for epoch in range(10): # 根据实际情况调整训练轮数
for batch in train_dataloader:
optimizer.zero_grad()
inputs = {'input_ids': batch[0],
'attention_mask': batch[1],
'labels': batch[2]}
outputs = model(**inputs)
loss = outputs.loss
loss.backward()
optimizer.step()
scheduler.step()
# 测试模型
test_dataloader = torch.utils.data.DataLoader(test_dataset, batch_size=16, shuffle=False)
model.eval()
predictions = []
with torch.no_grad():
for batch in test_dataloader:
inputs = {'input_ids': batch[0],
'attention_mask': batch[1]}
outputs = model(**inputs)
_, predicted_labels = torch.max(outputs.logits, dim=1)
predictions.extend(predicted_labels.tolist())
# 打印预测结果
print(predictions)
```
在上面的代码中,你需要将 `data.csv` 替换为你的实际数据文件名,并根据实际情况调整特征列和标签列的提取方式。此外,还需要根据实际情况调整预训练模型的选择和训练参数的设置。此示例使用了BERT模型进行文本分类任务,你可以根据需要选择其他模型和调整相关参数。
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