class R_NN(nn.Module): def __init__(self, in_dim, n_class): super(R_NN, self).__init__() self.logstic = nn.Linear(in_dim, n_class) self.predict=nn.Sigmoid() def forward(self, x): out = self.logstic(x) out = out.squeeze(1) #降维 return out
时间: 2023-06-08 10:05:27 浏览: 51
这段代码是一个定制化的PyTorch神经网络模块。该模块名为R_NN,有两个输入参数:in_dim表示输入数据的维度,n_class表示分类的数量。在初始化函数中,调用了super()函数来获得父类nn.Module的属性和方法,然后定义了一个线性层(logstic)和一个Sigmoid层(predict)。在前向传播函数forward()中,对输入数据x进行线性变换,再使用squeeze()函数将一维的输出向量压缩为一个标量。
相关问题
class Linear_BBB(nn.Module):
class Linear_BBB(nn.Module)是一个自定义的类,它是继承自nn.Module的一个子类。nn.Module是PyTorch中用于构建神经网络模型的基类。
在这个类中,你可以定义一个线性层(Linear layer),并且使用变分贝叶斯(Variational Bayesian)方法对其进行建模。变分贝叶斯是一种用于估计模型参数不确定性的方法,它可以用来量化模型的不确定性,并提供更可靠的预测结果。
在Linear_BBB类中,你可以定义模型的结构和参数,并实现前向传播函数。以下是一个示例代码:
```python
import torch
import torch.nn as nn
class Linear_BBB(nn.Module):
def __init__(self, input_dim, output_dim):
super(Linear_BBB, self).__init__()
self.input_dim = input_dim
self.output_dim = output_dim
self.W_mu = nn.Parameter(torch.Tensor(output_dim, input_dim))
self.W_rho = nn.Parameter(torch.Tensor(output_dim, input_dim))
self.b_mu = nn.Parameter(torch.Tensor(output_dim))
self.b_rho = nn.Parameter(torch.Tensor(output_dim))
self.reset_parameters()
def reset_parameters(self):
nn.init.kaiming_uniform_(self.W_mu, a=math.sqrt(5))
nn.init.kaiming_uniform_(self.W_rho, a=math.sqrt(5))
fan_in, _ = nn.init._calculate_fan_in_and_fan_out(self.W_mu)
bound = 1 / math.sqrt(fan_in)
nn.init.uniform_(self.b_mu, -bound, bound)
nn.init.uniform_(self.b_rho, -bound, bound)
def forward(self, x):
epsilon_W = torch.randn_like(self.W_mu)
epsilon_b = torch.randn_like(self.b_mu)
W = self.W_mu + torch.log1p(torch.exp(self.W_rho)) * epsilon_W
b = self.b_mu + torch.log1p(torch.exp(self.b_rho)) * epsilon_b
return torch.matmul(x, W.t()) + b
```
在这个示例中,Linear_BBB类接受两个参数:input_dim和output_dim,分别表示输入和输出的维度。在初始化函数中,我们定义了模型的参数W和b,并使用均匀分布进行初始化。在前向传播函数中,我们使用变分贝叶斯方法对参数进行采样,并计算线性变换的结果。
这只是一个简单的示例,你可以根据自己的需求来定义更复杂的模型结构和参数。希望对你有帮助!
class Partial_conv3(nn.Module): def __init__(self, dim, n_div, forward): super().__init__() self.dim_conv3 = dim // n_div self.dim_untouched = dim - self.dim_conv3 self.partial_conv3 = nn.Conv2d(self.dim_conv3, self.dim_conv3, 3, 1, 1, bias=False) if forward == 'slicing': self.forward = self.forward_slicing elif forward == 'split_cat': self.forward = self.forward_split_cat else: raise NotImplementedError def forward_slicing(self, x: Tensor) -> Tensor: # only for inference x = x.clone() # !!! Keep the original input intact for the residual connection later x[:, :self.dim_conv3, :, :] = self.partial_conv3(x[:, :self.dim_conv3, :, :]) return x def forward_split_cat(self, x: Tensor) -> Tensor: x1, x2 = torch.split(x, [self.dim_conv3, self.dim_untouched], dim=1) x1 = self.partial_conv3(x1) x = torch.cat((x1, x2), 1) return x 在这段代码中插入全局平均池化做通道增强的模块
可以将全局平均池化放在每个 forward 函数的最后,对每个 channel 进行平均池化操作,然后将结果与未被改变的 channel 拼接起来,得到增强后的输出。修改后的代码如下:
```
class Partial_conv3(nn.Module):
def __init__(self, dim, n_div, forward):
super().__init__()
self.dim_conv3 = dim // n_div
self.dim_untouched = dim - self.dim_conv3
self.partial_conv3 = nn.Conv2d(self.dim_conv3, self.dim_conv3, 3, 1, 1, bias=False)
self.global_avg_pool = nn.AdaptiveAvgPool2d((1, 1)) # 添加全局平均池化层
if forward == 'slicing':
self.forward = self.forward_slicing
elif forward == 'split_cat':
self.forward = self.forward_split_cat
else:
raise NotImplementedError
def forward_slicing(self, x: Tensor) -> Tensor:
# only for inference
x = x.clone() # !!! Keep the original input intact for the residual connection later
x[:, :self.dim_conv3, :, :] = self.partial_conv3(x[:, :self.dim_conv3, :, :])
x[:, :self.dim_conv3, :, :] = self.global_avg_pool(x[:, :self.dim_conv3, :, :]) # 添加全局平均池化
x = torch.cat((x, x[:, self.dim_conv3:, :, :]), 1)
return x
def forward_split_cat(self, x: Tensor) -> Tensor:
x1, x2 = torch.split(x, [self.dim_conv3, self.dim_untouched], dim=1)
x1 = self.partial_conv3(x1)
x1 = self.global_avg_pool(x1) # 添加全局平均池化
x = torch.cat((x1, x2), 1)
return x
```