@AlphaBetaGamma96
I tried:
Xnumerator = torch.cross(Xleft, Xright, dim=1)
norm2 = Xnumerator.pow(2).sum(dim=1).sqrt()
nu = Xnumerator / norm2

I am getting this error:

nu = Xnumerator / norm2
RuntimeError: The size of tensor a (3) must match the size of tensor b (60) at non-singleton dimension 1

Xnumerator → torch.Size([60, 3, 240, 320])
norm2 → torch.Size([60, 240, 320])