Traceback (most recent call last):


 "tools/train.py", line 181, in <module>

main()


 "tools/train.py", line 177, in main

meta=meta)


 "c:\users\asus\mmdetection\mmdet\apis\train.py", line 150, in train_detector

runner.run(data_loaders, cfg.workflow, cfg.total_epochs)


 "D:\anaconda\envs\mmd2\lib\site-packages\mmcv\runner\epoch_based_runner.py", line 125, in run

epoch_runner(data_loaders[i], **kwargs)


 "D:\anaconda\envs\mmd2\lib\site-packages\mmcv\runner\epoch_based_runner.py", line 47, in train

for i, data_batch in enumerate(self.data_loader):


 "D:\anaconda\envs\mmd2\lib\site-packages\torch\utils\data\dataloader.py", line 291, in __iter__

return _MultiProcessingDataLoaderIter(self)


 "D:\anaconda\envs\mmd2\lib\site-packages\torch\utils\data\dataloader.py", line 764, in __init__

self._try_put_index()


 "D:\anaconda\envs\mmd2\lib\site-packages\torch\utils\data\dataloader.py", line 994, in _try_put_index

index = self._next_index()


 "D:\anaconda\envs\mmd2\lib\site-packages\torch\utils\data\dataloader.py", line 357, in _next_index

return next(self._sampler_iter)
# may raise StopIteration


 "D:\anaconda\envs\mmd2\lib\site-packages\torch\utils\data\sampler.py", line 208, in __iter__

for idx in self.sampler:


 "c:\users\asus\mmdetection\mmdet\datasets\samplers\group_sampler.py", line 36, in __iter__

indices = np.concatenate(indices)


 "<__array_function__ internals>", line 6, in concatenate
ValueError: need at least one array to concatenate
Traceback (most recent call last):


 "hub/compute/tests/test_transform.py", line 284, in <module>

test_threaded()


 "hub/compute/tests/test_transform.py", line 88, in test_threaded

create_classification_dataset(ds_init).store(


 "/Users/davitb/Git/Hub/hub/compute/transform.py", line 246, in store

ds = self.upload(results, url=url, token=token, progressbar=progressbar)


 "/Users/davitb/Git/Hub/hub/compute/transform.py", line 177, in upload

list(self.map(upload_chunk, index_batched_values))


 "/Users/davitb/Library/Python/3.8/lib/python/site-packages/pathos/threading.py", line 134, in map

return _pool.map(star(f), zip(*args)) # chunksize


 "/Users/davitb/Library/Python/3.8/lib/python/site-packages/multiprocess/pool.py", line 364, in map

return self._map_async(func, iterable, mapstar, chunksize).get()


 "/Users/davitb/Library/Python/3.8/lib/python/site-packages/multiprocess/pool.py", line 771, in get

raise self._value


 "/Users/davitb/Library/Python/3.8/lib/python/site-packages/multiprocess/pool.py", line 125, in worker

result = (True, func(*args, **kwds))


 "/Users/davitb/Library/Python/3.8/lib/python/site-packages/multiprocess/pool.py", line 48, in mapstar

return list(map(*args))


 "/Users/davitb/Library/Python/3.8/lib/python/site-packages/pathos/helpers/mp_helper.py", line 15, in <lambda>

func = lambda args: f(*args)


 "/Users/davitb/Git/Hub/hub/compute/transform.py", line 167, in upload_chunk

ds[key, i * length + k] = el


 "/Users/davitb/Git/Hub/hub/api/dataset.py", line 316, in __setitem__

self._tensors[subpath][slice_list] = value


 "/Users/davitb/Git/Hub/hub/store/dynamic_tensor.py", line 207, in __setitem__

self._dynamic_tensor[slice_[0]]


 "/usr/local/lib/python3.8/site-packages/zarr/core.py", line 571, in __getitem__

return self.get_basic_selection(selection, fields=fields)


 "/usr/local/lib/python3.8/site-packages/zarr/core.py", line 696, in get_basic_selection

return self._get_basic_selection_nd(selection=selection, out=out,


 "/usr/local/lib/python3.8/site-packages/zarr/core.py", line 739, in _get_basic_selection_nd

return self._get_selection(indexer=indexer, out=out, fields=fields)


 "/usr/local/lib/python3.8/site-packages/zarr/core.py", line 1028, in _get_selection

self._chunk_getitem(chunk_coords, chunk_selection, out, out_selection,


 "/usr/local/lib/python3.8/site-packages/zarr/core.py", line 1649, in _chunk_getitem

self._process_chunk(out, cdata, chunk_selection, drop_axes,


 "/usr/local/lib/python3.8/site-packages/zarr/core.py", line 1592, in _process_chunk

chunk = self._decode_chunk(cdata)


 "/usr/local/lib/python3.8/site-packages/zarr/core.py", line 1802, in _decode_chunk

chunk = chunk.reshape(self._chunks, order=self._order)
ValueError: cannot reshape array of size 0 into shape (50,3)
