Codebook: Are You Shor This Works?

Codebook
1

Ask here about the “Are You Shor This Works?” Codebook topic from the “Quantum Error Correction” module.

2

Hello,
Here is my code for shor’s code

    ##################
    # YOUR CODE HERE #
    ##################
    qml.QubitStateVector(state, wires=[0])
    qml.CNOT(0,3)
    qml.CNOT(0,6)
    qml.Hadamard(0)
    qml.Hadamard(3)
    qml.Hadamard(6)
    qml.CNOT(0,1)
    qml.CNOT(0,2)
    qml.CNOT(3,4)
    qml.CNOT(3,5)
    qml.CNOT(6,7)
    qml.CNOT(6,8)
    
    # apply the error
    for err in error(error_type=error_type, wires=wires):
        err

    ##################
    # YOUR CODE HERE #
    ##################
    qml.CNOT(0,1)
    qml.CNOT(0,2)
    qml.Toffoli([1,2,0])
    qml.CNOT(3,4)
    qml.CNOT(3,5)
    qml.Toffoli([4,5,3])
    qml.CNOT(6,7)
    qml.CNOT(6,8)
    qml.Toffoli([7,8,6])
    qml.Hadamard(0)
    qml.Hadamard(3)
    qml.Hadamard(6)
    qml.CNOT(0,3)
    qml.CNOT(0,6)
    qml.Toffoli([6,3,0])

I get an error: ‘int’ object is not subscriptable, and I can’t understand where it comes from

3

I have a second question : Is there a way to convert qml.probs’s output to a numpy array ?

4

Hi @yoshypdf ,

The error “‘int’ object is not subscriptable” arises because the CNOTs don’t take two arguments, they take a single argument which is a list of wires.

So instead of having qml.CNOT(0,3) you should write qml.CNOT([0,3]).

I hope this helps!

Note: I’ve blurred out your answer to avoid spoilers for others.

1 Like
5

The output should indeed be a numpy array when you’re using the Numpy interface (which is what we use in the Codebook).