oh you were right!!! That line produced Nan values. Now I see why did you ask me to print out.
------------self.w--------
Parameter containing:
tensor([[[[-0.3731, 2.3884, 0.9738],
[-0.9576, 0.7097, -0.3284],
[-0.1237, -0.4981, -0.0105]]]], requires_grad=True)
---------self.myParam--------
Parameter containing:
tensor([0.2613], requires_grad=True)
---self.w**self.myParam---
tensor([[[[ nan, 1.2555, 0.9931],
[ nan, 0.9143, nan],
[ nan, nan, nan]]]], grad_fn=<PowBackward1>)
----------tempVar---------
tensor([[[[ nan, 1.2555, 0.9931],
[ nan, 0.9143, nan],
[-0.1237, nan, -0.0105]]]], grad_fn=<SWhereBackward>)