torch.angle
torch.angle(input, *, out=None) -> Tensor
Computes the element-wise angle (in radians) of the given "input"
   tensor.
  \text{out}_{i} = angle(\text{input}_{i})

Parameters:
      input (Tensor) -- the input tensor.
Keyword Arguments:
      out (Tensor, optional) -- the output tensor.
Note:
 Starting in PyTorch 1.8, angle returns pi for negative real
 numbers, zero for non-negative real numbers, and propagates NaNs.
 Previously the function would return zero for all real numbers
 and not propagate floating-point NaNs.

Example:
  >>> torch.angle(torch.tensor([-1 + 1j, -2 + 2j, 3 - 3j]))*180/3.14159
  tensor([ 135.,  135,  -45])
