else: # 单标签分类 print('Epoch [{0:>3}/{1:>3}/{2:>5}]'.format(epoch + 1, config.num_epochs, total_batch), end=' ') print(' | loss: {:.4f}'.format(train_loss.item()), end='') result_train = evaluate(outputs, labels, config.classify_type) print(' | time: {:.4f}s'.format(get_time_dif(t))) # 验证集和训练集的准确率 vali_loss, result_vali = vali_test(config, model, vali_iter, LOSS) # 验证 test_loss, result_test = vali_test(config, model, test_iter, LOSS) # 测试
时间: 2024-04-17 15:27:25 浏览: 13
这段代码是在单标签分类情况下,在每个epoch的训练过程中输出训练集的损失值和评估结果,并计算验证集和测试集的损失值和评估结果。
首先,判断当前是单标签分类情况,进入else分支。然后,输出当前epoch的信息,包括当前epoch的索引、总的epoch数和进行到的batch数。通过`format()`函数将这些信息格式化打印出来。
接下来,输出训练集的损失值,通过`train_loss.item()`获取训练损失的数值,并使用`print()`函数将其打印出来。
然后,调用`evaluate()`函数对模型的输出结果和标签进行评估,得到评估结果`result_train`。通过`evaluate()`函数计算准确率等指标。
接下来,调用`vali_test()`函数对验证集和测试集进行评估。分别传入配置文件`config`、模型对象`model`、验证集迭代器`vali_iter`和测试集迭代器`test_iter`,以及损失函数`LOSS`。返回验证集和测试集的损失值和评估结果。
最后,将验证集和测试集的损失值和评估结果打印出来。
整个代码段的作用是在单标签分类情况下,输出训练集的损失值和评估结果,并计算验证集和测试集的损失值和评估结果。
相关问题
pytorch实现端到端分类任务:1000个样本,每个样本序列都有2000个数,标签序列是2000个0-4的数,五分类问题,TCN模型搭建
好的,以下是一个简单的PyTorch示例代码,用于使用TCN模型进行端到端分类任务:
```python
import torch
import torch.nn as nn
import torch.optim as optim
from torch.utils.data import Dataset, DataLoader
# 定义TCN模型
class TemporalConvNet(nn.Module):
def __init__(self, channels, kernel_size=2, dropout=0.2):
super(TemporalConvNet, self).__init__()
layers = []
num_levels = len(channels)
for i in range(num_levels):
dilation_size = 2 ** i
in_channels = channels[i-1] if i > 0 else 1
out_channels = channels[i]
layers += [nn.Conv1d(in_channels, out_channels, kernel_size, dilation=dilation_size)]
layers += [nn.ReLU()]
layers += [nn.Dropout(dropout)]
self.network = nn.Sequential(*layers)
def forward(self, x):
x = x.permute(0, 2, 1)
x = self.network(x)
x = x.permute(0, 2, 1)
return x
# 定义端到端分类模型
class TCNClassifier(nn.Module):
def __init__(self, input_size, num_classes, channels=[25]*8, kernel_size=2, dropout=0.2):
super(TCNClassifier, self).__init__()
self.tcn = TemporalConvNet(channels, kernel_size, dropout)
self.fc = nn.Linear(channels[-1], num_classes)
def forward(self, x):
x = self.tcn(x)
x = x[:, -1, :]
x = self.fc(x)
return x
# 定义数据集
class MyDataset(Dataset):
def __init__(self, data, targets):
self.data = data
self.targets = targets
def __getitem__(self, index):
x = torch.tensor(self.data[index], dtype=torch.float32)
y = torch.tensor(self.targets[index], dtype=torch.long)
return x, y
def __len__(self):
return len(self.data)
# 定义超参数
batch_size = 32
learning_rate = 0.01
num_epochs = 10
# 加载数据集
data = torch.randn(1000, 2000, 1)
targets = torch.randint(0, 5, (1000, 2000))
dataset = MyDataset(data, targets)
loader = DataLoader(dataset, batch_size=batch_size, shuffle=True)
# 定义模型和优化器
model = TCNClassifier(input_size=1, num_classes=5)
optimizer = optim.Adam(model.parameters(), lr=learning_rate)
# 训练模型
for epoch in range(num_epochs):
for batch_idx, (data, target) in enumerate(loader):
optimizer.zero_grad()
output = model(data)
loss = nn.functional.cross_entropy(output.permute(0, 2, 1), target)
loss.backward()
optimizer.step()
if batch_idx % 10 == 0:
print('Epoch [{}/{}], Batch [{}/{}], Loss: {:.4f}'.format(
epoch+1, num_epochs, batch_idx+1, len(loader), loss.item()))
```
该代码中定义了一个名为`TemporalConvNet`的TCN模型类,包含多个卷积层和激活函数。然后定义了一个名为`TCNClassifier`的端到端分类模型类,包含一个TCN模型和一个全连接层用于分类。接着定义了一些超参数,包括批量大小、学习率和训练轮数。然后使用PyTorch的`DataLoader`将数据集加载到内存中,并使用Adam优化器进行模型优化,使用交叉熵损失函数计算损失。最后,在训练过程中打印训练损失。
https://aistudio.baidu.com/aistudio/datasetdetail/177317以此网址数据集为基础,用pytorch编写一份中文字体识别代码
好的,以下是使用 PyTorch 实现中文字体识别的代码,主要分为数据处理、模型定义和训练三个部分。代码中使用了 Convolutional Neural Networks (CNN) 模型进行中文字体识别。
```python
import torch
import torch.nn as nn
import torch.optim as optim
from torch.utils.data import DataLoader, Dataset
import torchvision.transforms as transforms
from PIL import Image
import os
# 数据处理
class ChineseFontDataset(Dataset):
def __init__(self, data_dir, transform=None):
self.imgs = os.listdir(data_dir)
self.data_dir = data_dir
self.transform = transform
def __getitem__(self, index):
img_path = os.path.join(self.data_dir, self.imgs[index])
img = Image.open(img_path).convert('RGB')
if self.transform is not None:
img = self.transform(img)
target = int(self.imgs[index].split('_')[0])
return img, target
def __len__(self):
return len(self.imgs)
# 模型定义
class ChineseFontCNN(nn.Module):
def __init__(self):
super(ChineseFontCNN, self).__init__()
self.conv1 = nn.Conv2d(in_channels=3, out_channels=64, kernel_size=3)
self.conv2 = nn.Conv2d(in_channels=64, out_channels=128, kernel_size=3)
self.conv3 = nn.Conv2d(in_channels=128, out_channels=256, kernel_size=3)
self.fc1 = nn.Linear(in_features=256*10*10, out_features=512)
self.fc2 = nn.Linear(in_features=512, out_features=100)
self.dropout = nn.Dropout(p=0.5)
self.relu = nn.ReLU()
def forward(self, x):
x = self.conv1(x)
x = self.relu(x)
x = self.conv2(x)
x = self.relu(x)
x = self.conv3(x)
x = self.relu(x)
x = x.view(-1, 256*10*10)
x = self.fc1(x)
x = self.relu(x)
x = self.dropout(x)
x = self.fc2(x)
return x
# 训练
def train(model, device, train_loader, optimizer, criterion, epoch):
model.train()
for batch_idx, (data, target) in enumerate(train_loader):
data, target = data.to(device), target.to(device)
optimizer.zero_grad()
output = model(data)
loss = criterion(output, target)
loss.backward()
optimizer.step()
if batch_idx % 100 == 0:
print('Train Epoch: {} [{}/{} ({:.0f}%)]\tLoss: {:.6f}'.format(
epoch, batch_idx * len(data), len(train_loader.dataset),
100. * batch_idx / len(train_loader), loss.item()))
if __name__ == '__main__':
data_dir = './ChineseFonts'
transform = transforms.Compose([
transforms.Resize(size=(100, 100)),
transforms.ToTensor(),
transforms.Normalize(mean=[0.5, 0.5, 0.5], std=[0.5, 0.5, 0.5])
])
dataset = ChineseFontDataset(data_dir=data_dir, transform=transform)
train_loader = DataLoader(dataset=dataset, batch_size=64, shuffle=True)
device = torch.device('cuda' if torch.cuda.is_available() else 'cpu')
model = ChineseFontCNN().to(device)
criterion = nn.CrossEntropyLoss()
optimizer = optim.Adam(model.parameters(), lr=0.001)
for epoch in range(1, 11):
train(model, device, train_loader, optimizer, criterion, epoch)
```
这份代码中,我们首先定义了一个数据处理类 `ChineseFontDataset`,用于读取数据集中的图片和标签,并进行数据增强和归一化操作。接着定义了一个卷积神经网络模型 `ChineseFontCNN`,该模型包含了三个卷积层和两个全连接层,最后输出分类结果。最后在 `train` 函数中进行模型的训练。
需要注意的是,由于中文字体识别数据集比较大,因此在训练过程中可能需要较长时间,可以根据自己的硬件配置和时间安排适当调整训练轮数和批次大小。