tensors and Python floats and complex Python numbers.
Parameters:
      d ("torch.dtype") -- the floating point dtype to make the
      default. Either torch.float32 or torch.float64.
-[ Example ]-



initial default for floating point is torch.float32
Python floats are interpreted as float32
torch.tensor([1.2, 3]).dtype
   torch.float32
initial default for floating point is torch.complex64
Complex Python numbers are interpreted as complex64
torch.tensor([1.2, 3j]).dtype
   torch.complex64
torch.set_default_dtype(torch.float64)
Python floats are now interpreted as float64
torch.tensor([1.2, 3]).dtype    # a new floating point tensor
   torch.float64
Complex Python numbers are now interpreted as complex128
torch.tensor([1.2, 3j]).dtype   # a new complex tensor
   torch.complex128


