>>> t = torch.tensor([-1.])
>>> torch.polygamma(1, t)
tensor([1.2914e+15])
>>> scipy.special.polygamma(1, t.numpy())
array([inf], dtype=float32)

>>> t = torch.tensor([-501.])
>>> torch.polygamma(1, t)
tensor([2.0831e+09])
>>> scipy.special.polygamma(1, t.numpy())
array([inf], dtype=float32)

>>> t = torch.tensor([-float('inf')])
>>> torch.polygamma(1, t)
tensor([nan])
>>> scipy.special.polygamma(1, t.numpy())
array([inf], dtype=float32)
>>> 

>>> t = torch.tensor([float('inf')])
>>> torch.polygamma(2, t)
tensor([nan])
>>> scipy.special.polygamma(2, t.numpy())
array([-0.], dtype=float32)
>>> torch.polygamma(3, t)
tensor([nan])
>>> scipy.special.polygamma(3, t.numpy())
array([0.], dtype=float32)
>>> torch.polygamma(4, t)
tensor([nan])
>>> scipy.special.polygamma(4, t.numpy())
array([-0.], dtype=float32)