首页 > 解决方案 > RuntimeError:/pytorch/torch/lib/TH/generic/THTensorMath.c:2864 处的张量大小不一致

问题描述

我正在尝试构建一个数据加载器,这就是它的样子

`class WhaleData(Dataset):
def __init__(self, data_file, root_dir , transform = None):
    self.csv_file = pd.read_csv(data_file)
    self.root_dir = root_dir
    self.transform = transforms.Resize(224)

def __len__(self):
    return len(os.listdir(self.root_dir))

def __getitem__(self, index):
    image = os.path.join(self.root_dir, self.csv_file['Image'][index])
    image = Image.open(image)
    image = self.transform(image)
    image = np.array(image)
    label  = self.csv_file['Image'][index]
    sample = {'image': image, 'label':label}
    return sample

trainset  = WhaleData(data_file = '/mnt/55-91e8-b2383e89165f/Ryan/1234/train.csv', 
     root_dir = '/mnt/4d55-91e8-b2383e89165f/Ryan/1234/train')
train_loader = torch.utils.data.DataLoader(trainset , batch_size = 4, shuffle =True,num_workers= 2)
for i, batch in enumerate(train_loader):
      (i, batch)

当我尝试运行这段代码时,我得到了这个错误,我确实得到了错误的性质,即我的所有图像可能不是相同的形状,而且我的图像也不是相同的形状,但如果我没有错只有当我将它们提供给网络时才会出现错误,因为图像都是不同的形状,但为什么会在这里抛出错误?任何关于我可能出错的地方的建议都会非常有帮助,如果需要,我很乐意提供任何额外的信息,

谢谢

RuntimeError: Traceback (most recent call last):
  File "/usr/local/lib/python3.5/dist-packages/torch/utils/data/dataloader.py", line 42, in _worker_loop
samples = collate_fn([dataset[i] for i in batch_indices])
  File "/usr/local/lib/python3.5/dist-packages/torch/utils/data/dataloader.py", line 116, in default_collate
    return {key: default_collate([d[key] for d in batch]) for key in batch[0]}
  File "/usr/local/lib/python3.5/dist-packages/torch/utils/data/dataloader.py", line 116, in <dictcomp>
    return {key: default_collate([d[key] for d in batch]) for key in batch[0]}
  File "/usr/local/lib/python3.5/dist-packages/torch/utils/data/dataloader.py", line 105, in default_collate
return torch.stack([torch.from_numpy(b) for b in batch], 0)
  File "/usr/local/lib/python3.5/dist-packages/torch/functional.py", line 64, in stack
    return torch.cat(inputs, dim)
RuntimeError: inconsistent tensor sizes at /pytorch/torch/lib/TH/generic    /THTensorMath.c:2864

标签: pythonpytorch

解决方案


当 PyTorch 尝试将图像堆叠到一个批处理张量中时会出现错误(参见torch.stack([torch.from_numpy(b) for b in batch], 0)您的跟踪)。正如您所提到的,由于图像具有不同的形状,因此堆叠失败(即,如果所有这些张量都具有形状,(B, H, W)则只能通过堆叠张量来创建张量)。B(H, W)


注意:我不完全确定,但设置batch_size=1fortorch.utils.data.DataLoader(...)可能会消除此特定错误,因为它可能不再需要调用torch.stack())。


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