Print random sample from dataloader in PyTorch

Question

I have a certain dataset loaded into a dataloader. For example, if I wanted to save 100 images from this dataloader, how should I iterate over the dataloader to save them?

Answer 1

Im not exactly sure what you are trying to do (maybe edit your question) but maybe this helps:

dataset = Dataset()
dataloader = torch.utils.data.DataLoader(
                 dataloader,
                 batch_size=32,
                 num_workers=1,
                 shuffle=True)

for samples, targets in dataloader:
    # 'sample' now is a batch of 32 (see batch-size above) elements of your dataset

Is this what you wanted? Hope so :)

Answer 2

Take dl as your dataloader.

If you want to print only the first batch you can do this:

for data, targets in dl:
  print #whatever you want
  break

But if you want the n-th batch you can do this:

for batch_idx, (data, target) in enumerate(train_loader):
  if batch_idx == n:
    print #whatever you want
    break