
minlength (int) -- optional, minimum number of bins.
        Should be non-negative.

Returns:
      a tensor of shape "Size([max(input) + 1])" if "input" is non-
      empty, else "Size(0)"
Return type:
      output (Tensor)
Example:
  >>> input = torch.randint(0, 8, (5,), dtype=torch.int64)
  >>> weights = torch.linspace(0, 1, steps=5)
  >>> input, weights
  (tensor([4, 3, 6, 3, 4]),
   tensor([ 0.0000,  0.2500,  0.5000,  0.7500,  1.0000])

  >>> torch.bincount(input)
  tensor([0, 0, 0, 2, 2, 0, 1])

  >>> input.bincount(weights)
  tensor([0.0000, 0.0000, 0.0000, 1.0000, 1.0000, 0.0000, 0.5000])
