TypeError: cannot unpack non-iterable NoneType object!

[xhpk]

hello ,when i train my dataset ,it always appear this erro:

Traceback (most recent call last): File "train.py", line 114, in main() File "train.py", line 105, in main model = train(cfg, args) File "train.py", line 44, in train model = do_train(cfg, model, train_loader, optimizer, scheduler, checkpointer, device, arguments, args) File "/data-output/SSD-master/ssd/engine/trainer.py", line 76, in dotrain for iteration, (images, targets, ) in enumerate(data_loader, start_iter): File "/opt/conda/lib/python3.7/site-packages/torch/utils/data/dataloader.py", line 363, in next data = self._next_data() File "/opt/conda/lib/python3.7/site-packages/torch/utils/data/dataloader.py", line 971, in _next_data return self._process_data(data) File "/opt/conda/lib/python3.7/site-packages/torch/utils/data/dataloader.py", line 1014, in _process_data data.reraise() File "/opt/conda/lib/python3.7/site-packages/torch/_utils.py", line 395, in reraise raise self.exc_type(msg) TypeError: Caught TypeError in DataLoader worker process 2. Original Traceback (most recent call last): File "/opt/conda/lib/python3.7/site-packages/torch/utils/data/_utils/worker.py", line 185, in _worker_loop data = fetcher.fetch(index) File "/opt/conda/lib/python3.7/site-packages/torch/utils/data/_utils/fetch.py", line 44, in fetch data = [self.dataset[idx] for idx in possibly_batched_index] File "/opt/conda/lib/python3.7/site-packages/torch/utils/data/_utils/fetch.py", line 44, in data = [self.dataset[idx] for idx in possibly_batched_index] File "/data-output/SSD-master/ssd/data/datasets/voc.py", line 46, in getitem image, boxes, labels = self.transform(image, boxes, labels) File "/data-output/SSD-master/ssd/data/transforms/transforms.py", line 75, in call img, boxes, labels = t(img, boxes, labels) TypeError: cannot unpack non-iterable NoneType object

[xhpk]

and sometime i also appear this error：

Original Traceback (most recent call last): File "/opt/conda/lib/python3.7/site-packages/torch/utils/data/_utils/worker.py", line 185, in _worker_loop data = fetcher.fetch(index) File "/opt/conda/lib/python3.7/site-packages/torch/utils/data/_utils/fetch.py", line 44, in fetch data = [self.dataset[idx] for idx in possibly_batched_index] File "/opt/conda/lib/python3.7/site-packages/torch/utils/data/_utils/fetch.py", line 44, in data = [self.dataset[idx] for idx in possibly_batched_index] File "/data-output/SSD-master/ssd/data/datasets/voc.py", line 47, in getitem boxes, labels = self.target_transform(boxes, labels) File "/data-output/SSD-master/ssd/data/transforms/target_transform.py", line 21, in call self.corner_form_priors, self.iou_threshold) File "/data-output/SSD-master/ssd/utils/box_utils.py", line 89, in assign_priors best_target_per_prior, best_target_per_prior_index = ious.max(1) RuntimeError: cannot perform reduction function max on tensor with no elements because the operation does not have an identity

[A154609]

I also have this problem, can l ask you how to deal with this? Thanks RuntimeError: cannot perform reduction function max on tensor with no elements because the operation does not have an identity

[A154609]

and sometime i also appear this error：

Original Traceback (most recent call last): File "/opt/conda/lib/python3.7/site-packages/torch/utils/data/_utils/worker.py", line 185, in _worker_loop data = fetcher.fetch(index) File "/opt/conda/lib/python3.7/site-packages/torch/utils/data/_utils/fetch.py", line 44, in fetch data = [self.dataset[idx] for idx in possibly_batched_index] File "/opt/conda/lib/python3.7/site-packages/torch/utils/data/_utils/fetch.py", line 44, in data = [self.dataset[idx] for idx in possibly_batched_index] File "/data-output/SSD-master/ssd/data/datasets/voc.py", line 47, in getitem boxes, labels = self.target_transform(boxes, labels) File "/data-output/SSD-master/ssd/data/transforms/target_transform.py", line 21, in call self.corner_form_priors, self.iou_threshold) File "/data-output/SSD-master/ssd/utils/box_utils.py", line 89, in assign_priors best_target_per_prior, best_target_per_prior_index = ious.max(1) RuntimeError: cannot perform reduction function max on tensor with no elements because the operation does not have an identity

I use this mothed to solve the problem, and my project can train successfully