Codercise I.9.2: why it is not possible to apply RX?

i found the solution for the this exercise but why is it not possible to apply the RX() for prepare_psi() function as shown here:
def prepare_psi():
qml.RX((2/3)*np.pi, wires=0)
compare to Codercise I.8.2 where the amplitude with different rotation angle.

Thank for help!

If you compute it the right way you will find that the angle is -2*(np.pi)/3 instead of 2*(np.pi)/3 but still even after doing that you will notice that it still doesn’t work eventhough it can create that state. I have tried it yesterday and I asked it in the forum as well. I am yet to have an answer.

Hi @Horacio , as @baudoin mentioned you can indeed use qml.RX but you must use the correct angle :smile:

If it still doesn’t work for you then make sure to check your y_basis_rotation() function.

danke @CatalinaAlbornoz

I’m glad my tip helped @Horacio !

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