Runtime error for, learner.fit_one_cycle

I got runtime error, when:
data.show_batch(rows=1, figsize=(7,7))
and when fit a learner:
RuntimeError: b should have at least 2 dimensions, but has 1 dimensions instead,
any ideas?

I got the same error!!
Did you find how to rectify it?

No I didn’t, I think that there might be a general problem with creating a image bunch,

Hi, I updated my fastai version to latest(1.0.45) and the error resolved !!

I tried this without success: :cold_sweat::sob:

How to update fastai? just reinstall?

I updated(just install as initial) to fastai 1.0.48 and the error fixed! but when I run learn.recorder.plot() , I get RuntimeError: CUDA error: device-side assert triggered

I am running latest version of fastai(v1.0.51) and I have some similar problem :confused:

Functions like:
-> show_batch()
-> fit_one_cycle()
-> fit()

Are not working. When I try to run my code I get the following error:
RuntimeError: DataLoader worker (pid 7604) is killed by signal: Unknown signal: 0.

I have tried the following fixes:
-> Updated all of my packages
-> reset num_workers back to 0
-> decrease batch_size to 32

But none of this seems to be working. Thoughts?

The same problem was resolved for me by passing


to the function that creates your DataBunch. This is important! Pass it to the DataBunch creator, not the function you have problem with. E.g. for the lesson1 of the course-v3 call:

data = ImageDataBunch.from_name_re(path_img, fnames, pat, ds_tfms=get_transforms(), size=224, bs=bs, num_workers=0).normalize(imagenet_stats)

Edit: also call fit_one_cycle(1) with parameter 1 to resolve the issue there.

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above solution worked for me passing the parameter num_workers=0 like as below
data_clas = TextClasDataBunch.from_df(path=path, train_df=df_train, valid_df=df_valid, test_df=df_test, tokenizer=tokenizer, vocab=hindi_vocab,bs=32,num_workers=0)
(error:File “”, line 1, in
File “C:\Users\Admin\anaconda3\envs\nlp_fastai\lib\multiprocessing\”, line 116, in spawn_main
exitcode = _main(fd, parent_sentinel)
File “C:\Users\Admin\anaconda3\envs\nlp_fastai\lib\multiprocessing\”, line 126, in _main
self = reduction.pickle.load(from_parent)
AttributeError: Can’t get attribute ‘HindiTokenizer’ on <module ‘main’ (built-in)>)