Function shuffle_dataset

slowfast/datasets/loader.py:173–202

" Shuffles the data. Args: loader (loader): data loader to perform shuffle. cur_epoch (int): number of the current epoch.

(loader, cur_epoch)

def shuffle_dataset(loader, cur_epoch):
    """ "
    Shuffles the data.
    Args:
        loader (loader): data loader to perform shuffle.
        cur_epoch (int): number of the current epoch.
    """
    if (
        loader._dataset_kind
        == torch.utils.data.dataloader._DatasetKind.Iterable
    ):
        if hasattr(loader.dataset, "sampler"):
            sampler = loader.dataset.sampler
        else:
            raise RuntimeError(
                "Unknown sampler for IterableDataset when shuffling dataset"
            )
    else:
        sampler = (
            loader.batch_sampler.sampler
            if isinstance(loader.batch_sampler, ShortCycleBatchSampler)
            else loader.sampler
        )
    assert isinstance(
        sampler, (RandomSampler, DistributedSampler)
    ), "Sampler type '{}' not supported".format(type(sampler))
    # RandomSampler handles shuffling automatically
    if isinstance(sampler, DistributedSampler):
        # DistributedSampler shuffles data based on epoch
        sampler.set_epoch(cur_epoch)