Incosistent Tensor size while loading data using data loader

I am training an OCR using RNN. I am supplying input data as word images of varying dimensions (since each word can be of different lengths) and the size of class labels of each input data is also not consistent. Since each word can have a different number of characters.

   tensor_word_dataset = WordImagesDataset(images, truths, transform = ToTensor())
   dataset_loader =,
                                            batch_size=16, shuffle=True,) 

This gives me the error:
RuntimeError: inconsistent tensor size at /py/conda-bld/pytorch_1493673470840/work/torch/lib/TH/generic/THTensorCopy.c:46

The image sizes of first 5 input labels and images respectively are:

 torch.Size([2]) torch.Size([32, 41])
 torch.Size([7]) torch.Size([32, 95])
 torch.Size([2]) torch.Size([32, 38])
 torch.Size([2]) torch.Size([32, 53])
 torch.Size([2]) torch.Size([32, 49])
 torch.Size([6]) torch.Size([32, 55])

Any suggestions as to how should I fix it. I want to shuffle the data and send it in batches instead of supplying them one at a time.

you might want to write a custom collate_fn, instead of the default one:

DataLoader takes a collate_fn as one of it’s keyword argument, the default value is default_collate

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