PyTorch different between ones_tensor = torch.ones((2, 3,)) and ones_tensor = torch.ones(2, 3)?
In PyTorch, what is different between
ones_tensor = torch.ones((2, 3,))

and
ones_tensor = torch.ones(2, 3)

?

There's no difference between the two. As stated in the documentation,

size (int...) – a sequence of integers defining the shape of the output tensor. Can be a variable number of arguments or a collection like a list or tuple.

If you test it, they both produce the same tensor with the same shape.
tensor([[1., 1., 1.],
    [1., 1., 1.]])

torch.Size([2, 3])

