Solved by ptrblck in post #6 
              
              
                This should work: 
x = torch.tensor([[[[1.1,1.2],[1.3,1.4]],
                   [[2.1,2.2],[2.3,2.4]],
                   [[3.1,3.2],[3.3,3.4]], 
                   [[4.1,4.2],[4.3,4.4]]],
                  [[[5.1,5.2],[5.3,5.4]],
                   [[6.1,6.2],[6.3,6.4]],
                   [[7.1,7.…