Tried running the Data-reuploading classifer example, but changed the backend to cirq by doing the following: dev = qml.device(“cirq.simulator”, wires=1) I am getting the following error: [image] I am not sure how to fix this issue but my goal is to build a similar sort of netowrk using Cirq ba…

Hi @thegajan , we’ve now fixed the data re-uploading tutorial, so the latest version should work correctly on the Cirq plugin :slightly_smiling_face: [image] Data-reuploading classifier — PennyLane Implement a single-qubit universal quantum classifier using PennyLane. …

Hi @thegajan ! I believe the Cirq plugin uses dev.state instead of dev._state. So replacing all occurances of dev._state with dev.state should fix the issue :slightly_smiling_face: This is something that we have on our roadmap to standardize, so by the next PennyLane release, all plugins should use …

Fixed! Thanks for the help! @josh however, now when I run the model now performance suffers greatly. [image] Is there a reason why Cirq backend performs so much worse than the default?

No worries @thegajan :slightly_smiling_face: Hmm, interesting, I’m not too sure. Can I ask what you have changed from the original tutorial, and what your new device looks like?

Hi @thegajan , I was mainly responsible for creating the Cirq plugin, but the behaviour you point out is rather confusing because we basically just access Cirq’s internal simulator, so there should no be qualitative difference between cirq.simulator and default.qubit. I’ll investigate this and look …

So, @thegajan , I found the reason for the bad performance. It is actually no bug in the PennyLane-Cirq plugin, but in the Data-reuploading classifier example. The example should not use the internal state of the simulator to make predictions, because this is not hardware-friendly. In this special c…

Problem using Cirq Plugin as Backend

PennyLane Plugins

thegajan November 22, 2019, 3:00am 5

@josh only changed the device (from default.qubit to cirq.simulator). Everything else is the same as the demo code.

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Problem using Cirq Plugin as Backend

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