import torch.nn as nn from torch.nn import functional as F class InvertedResidual(nn.Module): def __init__(self, in_features, out_features, stride, expand_ratio,activation=nn.ReLU6) : super(InvertedResidual, self).__init__() self.stride = stride assert stride in [1, 2] hidden_dim = in_features * expand_ratio self.is_residual = self.stride == 1 and in_features == out_features self.conv = nn.Sequential( # pw Point-wise nn.Conv2d(in_features, hidden_dim, 1, 1, 0, bias=False), nn.BatchNorm2d(hidden_dim), activation(inplace=True), # dw Depth-wise nn.Conv2d(hidden_dim, hidden_dim, 3, stride, 1, groups=hidden_dim, bias=False), nn.BatchNorm2d(hidden_dim), activation(inplace=True), # pw-linear, Point-wise linear nn.Conv2d(hidden_dim, out_features, 1, 1, 0, bias=False), nn.BatchNorm2d(out_features), ) def forward(self, x): if self.is_residual: return x + self.conv(x) else: return self.conv(x) print(InvertedResidual(1280, 512, stride=2, expand_ratio=6) )
时间: 2023-05-19 19:04:40 浏览: 75
这段代码定义了一个名为InvertedResidual的类,继承自nn.Module。该类包含了一些参数,如输入特征、输出特征、步长、扩张比例和激活函数。在类的初始化函数中,会根据这些参数创建一个卷积神经网络模型,并且判断是否需要进行残差连接。其中,nn.ReLU6是一个激活函数,nn.Sequential是一个容器,可以将多个层组合在一起。
相关问题
import torch import torch.nn.functional as F import torch.optim as optim from torchvision import transforms from torchvision import datasets from torch.utils. data import DataI oader 补全代码
下面是一个基本的 PyTorch MNIST 数据集训练代码示例,包括数据加载、模型定义、优化器和损失函数的定义以及训练过程。
```
import torch
import torch.nn as nn
import torch.nn.functional as F
import torch.optim as optim
from torchvision import transforms
from torchvision import datasets
from torch.utils.data import DataLoader
# 定义数据预处理
transform = transforms.Compose([
transforms.ToTensor(),
transforms.Normalize((0.1307,), (0.3081,))
])
# 加载数据集
train_dataset = datasets.MNIST('data', train=True, download=True, transform=transform)
test_dataset = datasets.MNIST('data', train=False, download=True, transform=transform)
train_loader = DataLoader(train_dataset, batch_size=64, shuffle=True)
test_loader = DataLoader(test_dataset, batch_size=64, shuffle=False)
# 定义模型
class Net(nn.Module):
def __init__(self):
super(Net, self).__init__()
self.conv1 = nn.Conv2d(1, 10, kernel_size=5)
self.conv2 = nn.Conv2d(10, 20, kernel_size=5)
self.fc1 = nn.Linear(320, 50)
self.fc2 = nn.Linear(50, 10)
def forward(self, x):
x = F.relu(F.max_pool2d(self.conv1(x), 2))
x = F.relu(F.max_pool2d(self.conv2(x), 2))
x = x.view(-1, 320)
x = F.relu(self.fc1(x))
x = self.fc2(x)
return F.log_softmax(x, dim=1)
net = Net()
# 定义优化器和损失函数
optimizer = optim.SGD(net.parameters(), lr=0.01, momentum=0.5)
criterion = nn.CrossEntropyLoss()
# 训练模型
def train(epoch):
net.train()
for batch_idx, (data, target) in enumerate(train_loader):
optimizer.zero_grad()
output = net(data)
loss = criterion(output, target)
loss.backward()
optimizer.step()
if batch_idx % 10 == 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()))
def test():
net.eval()
test_loss = 0
correct = 0
with torch.no_grad():
for data, target in test_loader:
output = net(data)
test_loss += criterion(output, target)
pred = output.argmax(dim=1, keepdim=True)
correct += pred.eq(target.view_as(pred)).sum().item()
test_loss /= len(test_loader.dataset)
print('\nTest set: Average loss: {:.4f}, Accuracy: {}/{} ({:.0f}%)\n'.format(
test_loss, correct, len(test_loader.dataset),
100. * correct / len(test_loader.dataset)))
for epoch in range(1, 5):
train(epoch)
test()
```
这是一个简单的卷积神经网络模型,用于对 MNIST 手写数字进行分类。训练过程中使用了交叉熵损失函数和随机梯度下降优化器。
import torch.nn as nn报错
这个错误可能是因为您没有正确安装 PyTorch 库或者没有正确引入 nn 模块。请确认您已经正确安装 PyTorch 库,并且在代码中正确引入了 nn 模块。例如:
```python
import torch
import torch.nn as nn
# 定义一个简单的神经网络模型
class Net(nn.Module):
def __init__(self):
super(Net, self).__init__()
self.fc1 = nn.Linear(10, 5)
self.fc2 = nn.Linear(5, 2)
def forward(self, x):
x = self.fc1(x)
x = nn.functional.relu(x)
x = self.fc2(x)
return x
# 实例化一个神经网络模型
net = Net()
```
如果您确认已经正确安装 PyTorch 库并且代码中正确引入了 nn 模块,但仍然遇到了问题,请检查您的代码是否存在其他语法错误或者逻辑错误。
相关推荐
![pdf](https://img-home.csdnimg.cn/images/20210720083512.png)
![pdf](https://img-home.csdnimg.cn/images/20210720083512.png)
![pdf](https://img-home.csdnimg.cn/images/20210720083512.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)