How to disable operations recording for the computation graph and also save previous operations

autograd
1

Hey, I need to apply a single operation on a tensor that I don’t want to be recorded for the computation graph. Also, I need that previous computation graph operations will be saved and won’t be deleted.

I tried to implement it with torch.no_grad() by this way:

import torch

t = torch.rand(1).requires_grad_()

# some previous tensor operations
t = t.add(0)

# operations that I dont want to be recorded
with torch.no_grad():
    t = t.sub(0)

the result is that t.grad_fn = None, but I would want it to be AddBackward0

is there any convenient way to do so? Thanks.