Solved by paragG in post #6 
              
              
                I found the bug in the code above. I needed to unsqueeze the input target tensors by the adding the line: target = target.unsqueeze(1) This changed the shape of the target tensor from torch.Size([num_of_rows]) to torch.Size([num_of_rows], 1) . The model trains fine now: 
[image] 
Thanks to those who…