Broadcast Expand Prevents Torchlayer from detecting Inputs Argument about pennylane HOT 3 CLOSED

Hi @waelitani ,

The order in which you add the decorators is very important. The @qml.qnode(dev) decorator should always be placed immediately above your quantum function. Then you can add other transforms above the QNode decorator. I tried it and it fixed the issue. let me know if it works for you!

from pennylane.

Placing the the qml.qnode decorator closest to the function definition seems to render the transform decorator ineffective. For example, adding @qml.transforms.broadcast_expand above it, would still throw the error:

ValueError: Broadcasting with MottonenStatePreparation is not supported. Please use the qml.transforms.broadcast_expand transform to use broadcasting with MottonenStatePreparation.

when using, say AmplitudeEmbedding, with the the lightning.qubit device.

I am not certain if this would be fixed by preserving the call signature, as fixed by 5857.

from pennylane.

This would tie into Issue #4460, which is a separate long standing issue we are needing to solve.

This may also tie into the fact we do gradient preprocessing before user transforms. I'll look into that.

from pennylane.