RuntimeError:mat1 和 mat2 形状无法相乘(64x1400 和 200x100)

RuntimeError: mat1 and mat2 shapes cannot be multiplied (64x1400 and 200x100)

提问人:Amir 提问时间:11/17/2023 最后编辑:Amir 更新时间:11/17/2023 访问量:41

问:

我正在研究一个多变量时间序列预测问题,使用 household_power_consumption.txt 数据集并实现 1D CNN 模型。加载数据的批处理大小为 64,序列长度为 50,特征为 7。预处理完成。下面提供了型号代码,请帮我出了什么问题?与模型的尺寸不匹配。

class CNN_ForecastNet(nn.Module):
    def __init__(self):
        super(CNN_ForecastNet,self).__init__()
        self.conv1d = nn.Conv1d(50,200,kernel_size=1)
        self.relu = nn.ReLU(inplace=True)
        self.drop_out = nn.Dropout(0.5)
        self.max_pooling = nn.MaxPool1d(1)
        self.fc1 = nn.Linear(200,100)
        self.fc2 = nn.Linear(100,1)
        
    def forward(self,x):
        x = self.conv1d(x)
        x = self.relu(x)
        x = self.drop_out(x)
        x = self.max_pooling(x)
        x = x.view(x.size(0),-1)
        x = self.fc1(x)
        x = self.relu(x)
        x = self.fc2(x)
        
        return x
    
    
model = CNN_ForecastNet()
train_losses = []
valid_losses = []
def Train():
    
    running_loss = .0
    
    model.train()
    
    for idx, (inputs,labels) in enumerate(train_loader):
        optimizer.zero_grad()
        preds = model(inputs.float())
        loss = criterion(preds,labels)
        loss.backward()
        optimizer.step()
        running_loss += loss
        
    train_loss = running_loss/len(train_loader)
    train_losses.append(train_loss.detach().numpy())
    
    print(f'train_loss {train_loss}')
    
def Valid():
    running_loss = .0
    
    model.eval()
    
    with torch.no_grad():
        for idx, (inputs, labels) in enumerate(test_loader):
            optimizer.zero_grad()
            preds = model(inputs.float())
            loss = criterion(preds,labels)
            running_loss += loss
            
        valid_loss = running_loss/len(test_loader)
        valid_losses.append(valid_loss.detach().numpy())
        print(f'valid_loss {valid_loss}')

epochs = 10
for epoch in range(epochs):
  if epoch % 2==0:

    print('epochs {}/{}'.format(epoch+1,epochs))
    Train()
    Valid()
    gc.collect()

错误如下所示

Traceback (most recent call last):

  Cell In[15], line 73
    Train()

  Cell In[15], line 41 in Train
    preds = model(inputs.float())

  File ~\anaconda3\Lib\site-packages\torch\nn\modules\module.py:1501 in _call_impl
    return forward_call(*args, **kwargs)

  Cell In[15], line 17 in forward
    x = self.fc1(x)

  File ~\anaconda3\Lib\site-packages\torch\nn\modules\module.py:1501 in _call_impl
    return forward_call(*args, **kwargs)

  File ~\anaconda3\Lib\site-packages\torch\nn\modules\linear.py:114 in forward
    return F.linear(input, self.weight, self.bias)

RuntimeError: mat1 and mat2 shapes cannot be multiplied (64x1400 and 200x100)
机器学习 深度学习 pytorch 神经网络 conv-neural-network

评论


答:

0赞 khushi-411 11/17/2023 #1

看起来 RuntimeError 是由于维度不匹配造成的。要解决此错误,您必须将输入要素 (in_features) 更改为 1400。self.fc1

希望它能解决您的问题。谢谢!

评论

0赞 Amir 11/17/2023
谢谢你,先生,问题解决了。但是,我有点困惑。在卷积层中,我们的输出大小为 200。但是根据你提到的,我用1400作为全连接层,调整后它就工作了。我想知道为什么我们没有直接将卷积层(即 200)的输出输入到第一个全连接层中?
0赞 khushi-411 11/18/2023
这是因为在调用 之前,您正在使用 size [batch size, 1400] 创建张量,其中 1400 是训练数据的特征数。您可以在创建张量时更改 self.fc1 的in_features或更改输入特征。self.fc1x.view(x.size(0),-1)