Porting to PyTorch

[nithya4]

I tried porting the code to PyTorch, specifically the Tensorflow version. The latter works perfectly.
But with PyTorch when I use optim.LBFGS, I run into exploding gradients/no updates on the target.
The error is in the update:
151
152 #update scale of initial Hessian approximation
--> 153 H_diag = ys / y.dot(y) # (y*y)
154
155 # compute the approximate (L-BFGS) inverse Hessian

ZeroDivisionError: float division by zero

I am running this on CPU only for the time being - macOS 10.13.1 64 bit.
Any insights on why this may be happening?

[sidak]

Hi @nithya4 ! Were you able to resolve this issue? Thanks! :)