在jupyter notebook中使用Resnet 101 网络结构替换 Resnet 50 网络结构，请给出详细的代码替换过程

在使用Resnet 101替换Resnet 50的过程中，需要先下载相应的预训练模型权重参数，然后在代码中加载该模型，替换掉原来的Resnet 50模型即可。下面是详细的代码替换过程：

1. 安装相应的PyTorch和torchvision包

!pip install torch torchvision

2. 导入相关的包

import torch
import torchvision.models as models

3. 下载Resnet 101预训练模型权重参数

resnet101 = models.resnet101(pretrained=True)

4. 替换模型

# 替换最后一层全连接层
resnet101.fc = torch.nn.Linear(in_features=2048, out_features=1000, bias=True)

5. 测试新模型

# 加载测试数据
test_input = torch.randn(1, 3, 224, 224)

# 测试新模型
output = resnet101(test_input)
print(output.shape)

以上就是在jupyter notebook中使用Resnet 101网络结构替换Resnet 50网络结构的详细代码替换过程。需要注意的是，替换模型后需要重新训练模型或者fine-tune模型，以适应具体的场景和任务需求。

相关问题

在jupyter notebook中使用Resnet 101替换Resnet 50

可以通过以下步骤在Jupyter Notebook中使用ResNet 101替换ResNet 50：

1. 首先，确保你已经安装了相应的Python库和框架，比如PyTorch、torchvision等。

2. 下载ResNet 101的预训练模型，可以在torchvision库中找到。

import torchvision.models as models

resnet101 = models.resnet101(pretrained=True)

3. 定义新的模型，将ResNet 101作为主干网络。

import torch.nn as nn

class NewModel(nn.Module):
    def __init__(self):
        super(NewModel, self).__init__()
        self.resnet101 = models.resnet101(pretrained=True)
        self.fc = nn.Linear(1000, 10) # 假设最后一层为10分类问题

    def forward(self, x):
        x = self.resnet101(x)
        x = self.fc(x)
        return x

4. 加载数据集，训练新模型，并保存模型。

# 加载数据集
train_loader, test_loader = ...

# 定义新模型
model = NewModel()

# 定义损失函数和优化器
criterion = nn.CrossEntropyLoss()
optimizer = ...

# 训练模型
num_epochs = 10
for epoch in range(num_epochs):
    for data in train_loader:
        inputs, labels = data
        optimizer.zero_grad()
        outputs = model(inputs)
        loss = criterion(outputs, labels)
        loss.backward()
        optimizer.step()

# 保存模型
torch.save(model.state_dict(), 'new_model.pth')

以上是在Jupyter Notebook中使用ResNet 101替换ResNet 50的基本步骤，可以根据自己的需求进行修改和调整。

jupyter notebook中 Resnet 101 网络结构代码

以下是在 Jupyter Notebook 中使用 PyTorch 实现的 ResNet-101 网络结构代码：

import torch.nn as nn

class Bottleneck(nn.Module):
    expansion = 4
    
    def __init__(self, in_planes, planes, stride=1):
        super(Bottleneck, self).__init__()
        self.conv1 = nn.Conv2d(in_planes, planes, kernel_size=1, bias=False)
        self.bn1 = nn.BatchNorm2d(planes)
        self.conv2 = nn.Conv2d(planes, planes, kernel_size=3, stride=stride, padding=1, bias=False)
        self.bn2 = nn.BatchNorm2d(planes)
        self.conv3 = nn.Conv2d(planes, planes * self.expansion, kernel_size=1, bias=False)
        self.bn3 = nn.BatchNorm2d(planes * self.expansion)
        self.relu = nn.ReLU(inplace=True)
        self.shortcut = nn.Sequential()
        if stride != 1 or in_planes != planes * self.expansion:
            self.shortcut = nn.Sequential(
                nn.Conv2d(in_planes, planes * self.expansion, kernel_size=1, stride=stride, bias=False),
                nn.BatchNorm2d(planes * self.expansion)
            )
        
    def forward(self, x):
        out = self.relu(self.bn1(self.conv1(x)))
        out = self.relu(self.bn2(self.conv2(out)))
        out = self.bn3(self.conv3(out))
        out += self.shortcut(x)
        out = self.relu(out)
        return out

class ResNet(nn.Module):
    def __init__(self, block, num_blocks, num_classes=10):
        super(ResNet, self).__init__()
        self.in_planes = 64
        
        self.conv1 = nn.Conv2d(3, 64, kernel_size=3, stride=1, padding=1, bias=False)
        self.bn1 = nn.BatchNorm2d(64)
        self.layer1 = self._make_layer(block, 64, num_blocks[0], stride=1)
        self.layer2 = self._make_layer(block, 128, num_blocks[1], stride=2)
        self.layer3 = self._make_layer(block, 256, num_blocks[2], stride=2)
        self.layer4 = self._make_layer(block, 512, num_blocks[3], stride=2)
        self.linear = nn.Linear(512 * block.expansion, num_classes)
        
    def _make_layer(self, block, planes, num_blocks, stride):
        strides = [stride] + [1] * (num_blocks - 1)
        layers = []
        for stride in strides:
            layers.append(block(self.in_planes, planes, stride))
            self.in_planes = planes * block.expansion
        return nn.Sequential(*layers)
    
    def forward(self, x):
        out = self.bn1(self.conv1(x))
        out = self.layer1(out)
        out = self.layer2(out)
        out = self.layer3(out)
        out = self.layer4(out)
        out = nn.functional.avg_pool2d(out, out.size()[3])
        out = out.view(out.size(0), -1)
        out = self.linear(out)
        return out

def ResNet101():
    return ResNet(Bottleneck, [3, 4, 23, 3])

其中 `Bottleneck` 是 ResNet 中的一个基本模块，`ResNet` 是整个 ResNet 网络结构的实现，`ResNet101` 是 ResNet-101 的具体实例化。