proper conversion of Tensor to list

[malashinroman]

list(torch.Tensor) doesn't convert Tensor to list of scalars, but to list of Tensors.

I checked this is True for pytorch versions 1.12 and 2.0

[ins] In [6]: a = torch.Tensor([0,1])
[ins] In [7]: a.tolist()
Out[7]: [0.0, 1.0]
[ins] In [8]: list(a)
Out[8]: [tensor(0.), tensor(1.)]

That lead to the KeyError when I tried to used combined pytorch datsets, like this

    if args.reproduce_bugs:
        # substitute labels 0-9 with 10-19
        fmnist_test.targets += 10
        fmnist_train.targets += 10
        full_test = mnist_test + fmnist_test
        full_train = mnist_train + fmnist_train
        n_classes = 20
    else:
        full_test = mnist_test
        full_train = mnist_train
        n_classes = 10

    benchmark = nc_benchmark(
        full_train,
        full_test,
        n_experiences=n_classes // 2,
        task_labels=list(range(10)),
    )

I probably will open an issue, because the same probably will repeat at least for similar usage in

avalanche/benchmarks/utils/dataset_traversal_utils.py:191

[AntonioCarta]

Thanks! Looks good to me.

can you add a small unit test so that we can avoid a regression?

@lrzpellegrini can you also check this? Do you know if we have other places where we may have the same bug?

[lrzpellegrini]

Not that I am aware of. Alas, this is a common issue when dealing with elements that may be PyTorch Tensors.

[malashinroman]

@AntonioCarta, I will add unittest tomorrow.

*frankly saying in environment managed as documented I wasn't able to pass couple of fast tests

[AntonioCarta]

*frankly saying in environment managed as documented I wasn't able to pass couple of fast tests

If you think this is a general issue and not a problem with your environment, feel free to open a separate issue.

For this PR, you can run just your test with python -m unittest tests.your.module.TestClass.test_method

[malashinroman]

@AntonioCarta I've found that scenarios I used before are now deprecated, so I added test to verify type and content of TaskAwareSuperivsedClassificationDataset.targets_val_to_idx