torch.atleast_1d
torch.atleast_1d(*tensors)
Returns a 1-dimensional view of each input tensor with zero
   dimensions. Input tensors with one or more dimensions are returned
   as-is.
Parameters:
      input (Tensor or list of Tensors) --
Returns:
      output (Tensor or tuple of Tensors)
Example:
  >>> x = torch.arange(2)
  >>> x
  tensor([0, 1])
  >>> torch.atleast_1d(x)
  tensor([0, 1])
  >>> x = torch.tensor(1.)
  >>> x
  tensor(1.)
  >>> torch.atleast_1d(x)
  tensor([1.])
  >>> x = torch.tensor(0.5)
  >>> y = torch.tensor(1.)
  >>> torch.atleast_1d((x, y))
  (tensor([0.5000]), tensor([1.]))
