我正在使用数据加载器加载图像文件夹
图像文件夹由三个类别(标签)组成,即
'/root/ant/dsd.png'
'/root/ant/sfds.png'
...
……
'/root/bee/dsf.png'
……
..
'/根/乳清/sfd.png'
这里有 ant,bee,whey 三个类
通过执行上面的代码,我得到了一个错误,即输出和目标的大小不匹配
错误:预期输入 batch_size (3) 与目标 batch_size (1) 匹配。
我认为错误可能出在 trainloader 中,因为提取了不同形状不匹配的标签
data_transform = transforms.Compose([
transforms.Resize(size=28),
transforms.ToTensor()
])
kumda_dataset = datasets.ImageFolder(root='/content/gdrive/My Drive/Colab Notebooks/images',
transform=data_transform)
#train & test
train_size = int(0.8 * len(kumda_dataset))
test_size = len(kumda_dataset) - train_size
#splitting
train_dataset, test_dataset = torch.utils.data.random_split(kumda_dataset, [train_size, test_size])
trainloader = torch.utils.data.DataLoader(train_dataset , batch_size = 1, shuffle = True)
testloader = torch.utils.data.DataLoader(test_dataset , batch_size = 4, shuffle = False )
model=nn.Linear(784,1)
criterion=nn.CrossEntropyLoss()
optimizer=optim.SGD(model.parameters(),lr=0.01)
num=10
for epoch in range(num):
for i,(images,labels) in enumerate(trainloader):
images=images.reshape(-1,28*28)
output=model(images)
loss=criterion(output,labels)
optimizer.zero_grad()
loss.backward()
optimizer.step()
if(i+1%70==0):
print("Epoch: {}/{}, \tIteration: {}/{}, \tLoss: {}".format(epoch + 1, num, i + 1,len(dataset_loader), loss.item()))
提前感谢您解决