Hi. While running: https://pennylane.ai/qml/demos/tutorial_variational_classifier.html I get: ValueError: BasisState parameter must consist of 0 or 1 integers.

Hi @_risto . The error you’re describing has to do with the BasisState operation only accepting an array of integers (you can read more about it here ) representing a specific state. E.g., np.array([0, 1, 0]) prepares the state |010⟩. Could you provide me with the exact code that you’re trying to ru…

Hi @theodor I am running the code as it is provided in the demo: https://pennylane.ai/qml/demos/tutorial_variational_classifier.html I have made no changes to it.

Could you make sure that you’re running the latest version of PennyLane (run pip install pennylane --upgrade to update PennyLane), and also provide me with the output of qml.about() when using import pennylane as qml. You could also attempt to create a clean environment and run things from there.

Hi @_risto . Did you attempt to update PennyLane? You could also try to run the tutorial as a Python file, downloadable from the bottom or the right side of the tutorial page , to see if that works better (which could mean that there’s something going on with the Jupyter environment). I also see that…

Hi @theodor Yes, I have done as you said, but no success. For future references, how should I install packages: powershell powershell administrator anaconda anaconda adniminstrator ? If you look at Problem using the Forest plugin it seems I am also having problems installing packages to proper…

Hi @_risto , It’s up to you how you want to install packages, although the recommended ways are either to stick with using Anaconda (conda install package) or PyPI (pip install package). It’s also always a good idea to have separate environments for separate projects/tasks, and only install the nece…

Hi @theodor Than you for clarification. I have followed the guidance in a post before, but still I get the ValueError: BasisState parameter must consist of 0 or 1 integers.

Hi @_risto , I’m sorry, but I can’t really help you much more without knowing exactly what’s not working. If you can provide a minimal non-working example where this error shows up I could have a look at it (that is, remove as much code as possible from the tutorial and attempt to locate exactly whe…

Hi @theodor Here is where I get it: [image]

Variational classifier — PennyLane error

PennyLane Help

_risto June 29, 2021, 7:43pm 5

Hi @theodor

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Variational classifier — PennyLane error

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