I wanted to have CategoricalCrossentropyLoss as performed in TensorFlow but while
I’ve read answers from discuss but it’s I am not getting clearly what to do
here is what I tried
my outputs =
output_truth = np.ones((1,1024,15))

if we tried to find loss for above shape using 
tf.keras.losses.CategoricalCrossentropy()(output_from_model, output_truth) 
# we get answer with no error 

but if we same tried with pytorch 
torch.nn.CrossEntropyLoss()(torch.tensor(output_from_model) torch.tensor(output_truth))

we get following error
---------------------------------------------------------------------------
RuntimeError                              Traceback (most recent call last)
/tmp/ipykernel_33/1032697456.py in <module>
----> 1 torch.nn.CrossEntropyLoss()(torch.tensor(tf_outs.numpy()), torch.tensor(x[2].numpy()))

/opt/conda/lib/python3.7/site-packages/torch/nn/modules/module.py in _call_impl(self, *input, **kwargs)
   1049         if not (self._backward_hooks or self._forward_hooks or self._forward_pre_hooks or _global_backward_hooks
   1050                 or _global_forward_hooks or _global_forward_pre_hooks):
-> 1051             return forward_call(*input, **kwargs)
   1052         # Do not call functions when jit is used
   1053         full_backward_hooks, non_full_backward_hooks = [], []

/opt/conda/lib/python3.7/site-packages/torch/nn/modules/loss.py in forward(self, input, target)
   1119     def forward(self, input: Tensor, target: Tensor) -> Tensor:
   1120         return F.cross_entropy(input, target, weight=self.weight,
-> 1121                                ignore_index=self.ignore_index, reduction=self.reduction)
   1122 
   1123 

/opt/conda/lib/python3.7/site-packages/torch/nn/functional.py in cross_entropy(input, target, weight, size_average, ignore_index, reduce, reduction)
   2822     if size_average is not None or reduce is not None:
   2823         reduction = _Reduction.legacy_get_string(size_average, reduce)
-> 2824     return torch._C._nn.cross_entropy_loss(input, target, weight, _Reduction.get_enum(reduction), ignore_index)
   2825 
   2826 

RuntimeError: Expected target size [1, 15], got [1, 1024, 15]