Example:
  >>> a = torch.randint(10, (4,))
  >>> a
  tensor([6, 4, 7, 1])
  >>> torch.float_power(a, 2)
  tensor([36., 16., 49.,  1.], dtype=torch.float64)

  >>> a = torch.arange(1, 5)
  >>> a
  tensor([ 1,  2,  3,  4])
  >>> exp = torch.tensor([2, -3, 4, -5])
  >>> exp
  tensor([ 2, -3,  4, -5])
  >>> torch.float_power(a, exp)
  tensor([1.0000e+00, 1.2500e-01, 8.1000e+01, 9.7656e-04], dtype=torch.float64)
