self.data[self.size] = e 是否有问题
时间: 2024-01-19 07:03:00 浏览: 31
`self.data[self.size] = e` 这行代码是用于将元素 `e` 添加至线性表的末尾的,其实现是通过将元素 `e` 赋值给数组 `self.data` 中下标为 `self.size` 的位置。
可能会有一种情况是线性表已满,但是由于进行了扩容操作,此时线性表的容量已经增加,因此可以将元素 `e` 添加到下标为 `self.size` 的位置。如果不进行扩容操作而直接添加元素,可能会导致数组越界的问题。
相关问题
class CNN(nn.Module): def __init__(self,input_size,output_size): super(CNN, self).__init__() self.B = B self.relu = nn.ReLU(inplace=True) self.conv1 = nn.Sequential( nn.Conv1d(in_channels=input_size, out_channels=64, kernel_size=2), # 24 - 2 + 1 = 23 nn.ReLU(), nn.MaxPool1d(kernel_size=2, stride=1), # 23 - 2 + 1 = 22 ) self.conv2 = nn.Sequential( nn.Conv1d(in_channels=64, out_channels=128, kernel_size=2), # 22 - 2 + 1 = 21 nn.ReLU(), nn.MaxPool2d(kernel_size=2, stride=1), # 21 - 2 + 1 = 20 ) self.Linear1 = nn.Linear(self.B * 127 * 20, self.B * 50) self.Linear2 = nn.Linear(self.B * 50 , output_size) def forward(self, x): # [batch_size, n_features, data_len] x = x.permute(0, 2, 1) x = self.conv1(x) x = self.conv2(x) x = x.view(-1) x = self.Linear1(x) x = self.relu(x) x = self.Linear2(x) x = x.view(x.shape[0], -1) return x
这段代码定义了一个CNN模型,它包含了两个卷积层和两个全连接层。下面是对代码的解释:
```python
class CNN(nn.Module):
def __init__(self, input_size, output_size):
super(CNN, self).__init__()
self.B = B
self.relu = nn.ReLU(inplace=True)
self.conv1 = nn.Sequential(
nn.Conv1d(in_channels=input_size, out_channels=64, kernel_size=2), # 24 - 2 + 1 = 23
nn.ReLU(),
nn.MaxPool1d(kernel_size=2, stride=1), # 23 - 2 + 1 = 22
)
self.conv2 = nn.Sequential(
nn.Conv1d(in_channels=64, out_channels=128, kernel_size=2), # 22 - 2 + 1 = 21
nn.ReLU(),
nn.MaxPool2d(kernel_size=2, stride=1), # 21 - 2 + 1 = 20
)
self.Linear1 = nn.Linear(self.B * 127 * 20, self.B * 50)
self.Linear2 = nn.Linear(self.B * 50 , output_size)
def forward(self, x):
# [batch_size, n_features, data_len]
x = x.permute(0, 2, 1)
x = self.conv1(x)
x = self.conv2(x)
x = x.view(-1)
x = self.Linear1(x)
x = self.relu(x)
x = self.Linear2(x)
x = x.view(x.shape[0], -1)
return x
```
在构造函数`__init__`中,模型初始化了一些参数并定义了网络的各个层。其中,`self.conv1`是一个包含了一个卷积层、ReLU激活函数和最大池化层的序列。`self.conv2`也是一个类似的序列。`self.Linear1`和`self.Linear2`分别是两个全连接层。
在前向传播函数`forward`中,输入数据首先进行形状变换,然后通过卷积层和激活函数进行特征提取和降维。之后,将特征展平并通过全连接层进行预测。最后,输出结果进行形状变换以匹配预期的输出形状。
需要注意的是,代码中的一些变量(如`B`)没有给出具体的定义,你可能需要根据自己的需求进行修改。
希望这个解释对你有所帮助!如果还有其他问题,请随时提问。
基于300条数据用CNN多分类预测时,训练精度特别差,代码如下class Model(Module): def __init__(self): super(Model, self).__init__() self.conv1_1 = nn.Conv2d(in_channels=3,out_channels=64,kernel_size=(3,3),padding=1) self.bn1_1 = nn.BatchNorm2d(64) self.relu1_1 = nn.ReLU() self.pool1 = nn.MaxPool2d(kernel_size=4, stride=4) self.conv2_1 = nn.Conv2d(in_channels=64,out_channels=128,kernel_size=(3,3),padding=1) self.bn2_1 = nn.BatchNorm2d(128) self.relu2_1 = nn.ReLU() self.pool2 = nn.MaxPool2d(kernel_size=2, stride=2) self.conv3_1 = nn.Conv2d(in_channels=128,out_channels=256,kernel_size=(3,3),padding=1) self.bn3_1 = nn.BatchNorm2d(256) self.relu3_1 = nn.ReLU() self.pool3 = nn.MaxPool2d(kernel_size=2, stride=2) self.conv4_1 = nn.Conv2d(in_channels=256,out_channels=512,kernel_size=(3,3)) self.bn4_1 = nn.BatchNorm2d(512) self.relu4_1 = nn.ReLU() self.conv4_2 = nn.Conv2d(in_channels=512,out_channels=512,kernel_size=(3,3)) self.bn4_2 = nn.BatchNorm2d(512) self.relu4_2 = nn.ReLU() self.pool4 = nn.MaxPool2d(kernel_size=2, stride=2) self.conv5_1 = nn.Conv2d(in_channels=512,out_channels=512,kernel_size=(3,3)) self.bn5_1 = nn.BatchNorm2d(512) self.relu5_1 = nn.ReLU() self.conv5_2 = nn.Conv2d(in_channels=512,out_channels=512,kernel_size=(3,3)) self.bn5_2 = nn.BatchNorm2d(512) self.relu5_2 = nn.ReLU() self.pool5 = nn.AdaptiveAvgPool2d(5) self.dropout1 = nn.Dropout(p=0.3) self.fc1=nn.Linear(512*5*5,512) self.relu6=nn.ReLU() self.dropout2 = nn.Dropout(p=0.2) self.fc2=nn.Linear(512,141) ,具体如何修改代码
训练精度差可能是由于数据集太小,或者模型的训练过程不够充分。可以尝试以下几个方法:
1. 增加数据集:可以通过数据增强的方法来扩充数据集,比如随机裁剪、翻转、旋转等等。
2. 调整超参数:可以尝试调整学习率、优化器、dropout等超参数来提高模型的性能。
3. 调整网络结构:可以尝试增加卷积层、全连接层,或者使用更深的网络结构来提高模型的性能。
以下是代码的修改建议:
1. 增加数据增强:可以使用 torchvision.transforms 对图像进行随机裁剪、翻转等操作,来扩充数据集。
2. 调整学习率和优化器:可以尝试使用较小的学习率,并选择合适的优化器,比如 Adam。
3. 增加全连接层:可以在模型中增加一个全连接层来提高模型性能。
4. 增加正则化:可以使用 L2 正则化来防止过拟合。
修改后的代码如下:
```
import torch.nn.functional as F
import torchvision.transforms as transforms
class Model(Module):
def __init__(self):
super(Model, self).__init__()
self.conv1_1 = nn.Conv2d(in_channels=3,out_channels=64,kernel_size=(3,3),padding=1)
self.bn1_1 = nn.BatchNorm2d(64)
self.relu1_1 = nn.ReLU()
self.pool1 = nn.MaxPool2d(kernel_size=4, stride=4)
self.conv2_1 = nn.Conv2d(in_channels=64,out_channels=128,kernel_size=(3,3),padding=1)
self.bn2_1 = nn.BatchNorm2d(128)
self.relu2_1 = nn.ReLU()
self.pool2 = nn.MaxPool2d(kernel_size=2, stride=2)
self.conv3_1 = nn.Conv2d(in_channels=128,out_channels=256,kernel_size=(3,3),padding=1)
self.bn3_1 = nn.BatchNorm2d(256)
self.relu3_1 = nn.ReLU()
self.pool3 = nn.MaxPool2d(kernel_size=2, stride=2)
self.conv4_1 = nn.Conv2d(in_channels=256,out_channels=512,kernel_size=(3,3))
self.bn4_1 = nn.BatchNorm2d(512)
self.relu4_1 = nn.ReLU()
self.conv4_2 = nn.Conv2d(in_channels=512,out_channels=512,kernel_size=(3,3))
self.bn4_2 = nn.BatchNorm2d(512)
self.relu4_2 = nn.ReLU()
self.pool4 = nn.MaxPool2d(kernel_size=2, stride=2)
self.conv5_1 = nn.Conv2d(in_channels=512,out_channels=512,kernel_size=(3,3))
self.bn5_1 = nn.BatchNorm2d(512)
self.relu5_1 = nn.ReLU()
self.conv5_2 = nn.Conv2d(in_channels=512,out_channels=512,kernel_size=(3,3))
self.bn5_2 = nn.BatchNorm2d(512)
self.relu5_2 = nn.ReLU()
self.pool5 = nn.AdaptiveAvgPool2d(5)
self.dropout1 = nn.Dropout(p=0.3)
self.fc1=nn.Linear(512*5*5, 1024)
self.relu6=nn.ReLU()
self.dropout2 = nn.Dropout(p=0.2)
self.fc2=nn.Linear(1024, 141)
# 数据增强
self.transform = transforms.Compose([
transforms.RandomCrop(32, padding=4),
transforms.RandomHorizontalFlip(),
transforms.ToTensor(),
transforms.Normalize((0.5, 0.5, 0.5), (0.5, 0.5, 0.5))
])
def forward(self, x):
x = self.conv1_1(x)
x = self.bn1_1(x)
x = self.relu1_1(x)
x = self.pool1(x)
x = self.conv2_1(x)
x = self.bn2_1(x)
x = self.relu2_1(x)
x = self.pool2(x)
x = self.conv3_1(x)
x = self.bn3_1(x)
x = self.relu3_1(x)
x = self.pool3(x)
x = self.conv4_1(x)
x = self.bn4_1(x)
x = self.relu4_1(x)
x = self.conv4_2(x)
x = self.bn4_2(x)
x = self.relu4_2(x)
x = self.pool4(x)
x = self.conv5_1(x)
x = self.bn5_1(x)
x = self.relu5_1(x)
x = self.conv5_2(x)
x = self.bn5_2(x)
x = self.relu5_2(x)
x = self.pool5(x)
x = x.view(-1, 512*5*5)
x = self.dropout1(x)
x = self.fc1(x)
x = self.relu6(x)
x = self.dropout2(x)
x = self.fc2(x)
return x
```
在训练时,可以使用如下代码来进行数据增强:
```
trainset = torchvision.datasets.CIFAR10(root='./data', train=True,
download=True, transform=model.transform)
trainloader = torch.utils.data.DataLoader(trainset, batch_size=128,
shuffle=True, num_workers=2)
```
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)