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pythonpytorch

How to assign value to a zero dimensional torch tensor?

z = torch.tensor(1, dtype= torch.int64)
z[:] = 5

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
IndexError: slice() cannot be applied to a 0-dim tensor.

I'm trying to assign a value to a torch tensor but because it has zero dimensions the slice operator doesn't work. How do I assign a new value then?

Solution

  • You can do an in-place operation e.g. multiplication:

    z *= 5

    You can also directly assign the value to the underlying data property of the tensor:

    z.data = torch.tensor(5)

    Note that, autograd (Pytorch's backpropagation engine) would not track any computation made directly on a tensor's data attribute.