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Zero-dimensional tensor concatenation problem

See original GitHub issue

Hi there,

Thank you for the code!

While training the ResNet50 model using the market1501 dataset, I got the following Runtime error:

Traceback (most recent call last):
  File "examples/", line 232, in <module>
  File "examples/", line 151, in main
    trainer.train(epoch, train_loader, optimizer)
  File "/home/bxpan/.local/lib/python3.5/site-packages/open_reid-0.2.0-py3.5.egg/reid/", line 33, in train
  File "/home/bxpan/.local/lib/python3.5/site-packages/open_reid-0.2.0-py3.5.egg/reid/", line 83, in _forward
  File "/home/bxpan/.local/lib/python3.5/site-packages/torch/nn/modules/", line 491, in __call__
    result = self.forward(*input, **kwargs)
  File "/home/bxpan/.local/lib/python3.5/site-packages/open_reid-0.2.0-py3.5.egg/reid/loss/", line 26, in forward
RuntimeError: zero-dimensional tensor (at position 0) cannot be concatenated

The problem turned out to happen at this specific line of code in dist_ap = I have printed out dist_ap, which is a python list full of zero-dimensional (its printed-out size is: torch.Size([])) tensors (I used a batch-size of 64 so the list has a length of 64):

[tensor(0.2895, device='cuda:0'), tensor(0.3334, device='cuda:0'), tensor(0.3334, device='cuda:0'), tensor(0.3175, device='cuda:0'), tensor(0.3078, device='cuda:0'), tensor(0.3078, device='cuda:0'), tensor(0.3045, device='cuda:0'), tensor(0.3045, device='cuda:0'), tensor(0.2636, device='cuda:0'), tensor(0.2630, device='cuda:0'), tensor(0.2497, device='cuda:0'), tensor(0.2636, device='cuda:0'), tensor(0.2967, device='cuda:0'), tensor(0.2657, device='cuda:0'), tensor(0.2967, device='cuda:0'), tensor(0.2936, device='cuda:0'), tensor(0.3517, device='cuda:0'), tensor(0.2939, device='cuda:0'), tensor(0.3517, device='cuda:0'), tensor(0.3185, device='cuda:0'), tensor(0.3318, device='cuda:0'), tensor(0.3357, device='cuda:0'), tensor(0.3260, device='cuda:0'), tensor(0.3357, device='cuda:0'), tensor(0.2928, device='cuda:0'), tensor(0.2906, device='cuda:0'), tensor(0.2928, device='cuda:0'), tensor(0.2906, device='cuda:0'), tensor(0.1992, device='cuda:0'), tensor(0.2086, device='cuda:0'), tensor(0.2086, device='cuda:0'), tensor(0.2040, device='cuda:0'), tensor(0.2742, device='cuda:0'), tensor(0.2836, device='cuda:0'), tensor(0.3117, device='cuda:0'), tensor(0.3117, device='cuda:0'), tensor(0.2838, device='cuda:0'), tensor(0.2686, device='cuda:0'), tensor(0.2435, device='cuda:0'), tensor(0.2838, device='cuda:0'), tensor(0.3124, device='cuda:0'), tensor(0.3268, device='cuda:0'), tensor(0.3304, device='cuda:0'), tensor(0.3304, device='cuda:0'), tensor(0.2591, device='cuda:0'), tensor(0.2671, device='cuda:0'), tensor(0.2825, device='cuda:0'), tensor(0.2825, device='cuda:0'), tensor(0.3309, device='cuda:0'), tensor(0.2836, device='cuda:0'), tensor(0.3126, device='cuda:0'), tensor(0.3309, device='cuda:0'), tensor(0.3232, device='cuda:0'), tensor(0.3493, device='cuda:0'), tensor(0.3493, device='cuda:0'), tensor(0.3379, device='cuda:0'), tensor(0.3044, device='cuda:0'), tensor(0.3173, device='cuda:0'), tensor(0.3173, device='cuda:0'), tensor(0.3009, device='cuda:0'), tensor(0.2941, device='cuda:0'), tensor(0.3048, device='cuda:0'), tensor(0.3048, device='cuda:0'), tensor(0.2704, device='cuda:0')]

The values of the tensors seem to be of no problem, but the concatenation fails. Any idea about what the problem is?

Thank you very much.


Issue Analytics

  • State:open
  • Created 5 years ago
  • Reactions:11
  • Comments:12

github_iconTop GitHub Comments

frhfcommented, May 10, 2018


I got the same problem recently. I think it is connected to a newer version of pytorch.

What worked for me is replacing with torch.stack, but I am not entirely sure if this solution is unproblematic.

Regards Frank

wujunyi627commented, Mar 10, 2019

I can run the code in pytorch in 0.4.1 version. you need to change the image

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