Hi, I got the following error. Is there any clue what would cause 0 elements in grad_variable? Many Thanks
Traceback (most recent call last):
  File "train-ucf24.py", line 459, in <module>
    main()
  File "train-ucf24.py", line 178, in main
    train(args, net, optimizer, criterion, scheduler)
  File "train-ucf24.py", line 280, in train
    loss.backward()
  File "/home/rusu5516/.local/lib/python3.5/site-packages/torch/autograd/variable.py", line 167, in backward
    torch.autograd.backward(self, gradient, retain_graph, create_graph, retain_variables)
  File "/home/rusu5516/.local/lib/python3.5/site-packages/torch/autograd/__init__.py", line 99, in backward
    variables, grad_variables, retain_graph)
RuntimeError: invalid argument 2: size '[1]' is invalid for input with 0 elements at /pytorch/torch/lib/TH/THStorage.c:41