# Tag Info

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Here is a circuit that can create the desired state (similar ideas were discussed in this answer), if all mentioned measurements yield $|0\rangle$ state: or in a more compact form (the circuits are constructed via quirk). The first three qubits are ancillary qubits and the rest are the qubits where $|0_L\rangle$ will be created if after the measurements all ...

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If you click the CX gate itself, it will be surrounded by a dashed box with a pen symbol in the top right corner. If you click this pen you can choose which qubit is the target and which is the control by drag-and-drop.

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I think in this case you can split the experiments into multiple jobs. The idea is that you split measurement calibration circuits generated by complete_meas_cal into a number of batches, execute the first batch and use the corresponding results to initialize a measurement correction fitter with CompleteMeasFitter. Then you can use the CompleteMeasFitter....

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Yes it is possible! However you need to make some small changes to the circuit. In the paper An Experimental Study of Shor's Factoring Algorithm on IBM Q They have factored 12,21 and 35 using something called the Kitaev approach. In Shor's algorithm, you perform the QFT in such a manner that the entire answer is given to you at once. However if you instead ...

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This link was shared in the Qiskit Global Summer School Discord channel. https://join.slack.com/t/qiskit/shared_invite/zt-fybmq791-hYRopcSH6YetxycNPXgv~A I hope this works for you!

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I think the problem you are experiencing comes from Excel and not IBM Quantum Experience. Check this explanation, it explains why the bug you have happens, and ways to work around it. Hope this will help :) Edit : I think I found another workaround to your problem. Try this and tell me if this works for you: Download the CSV file but don't touch it yet. ...

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I'm not sure what your specific question is - the IBM Q processor does not implement an error correction scheme by default, so the theorem doesn't apply. Furthermore, the statistic provided in the Wikipedia page suggests this chip would be incapable of sufficiently depressing the error rate: At a 0.1% probability of a depolarizing error, the surface code ...

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Every rotation or controlled operation you perform on each individual qubit has an error associated to it, you can check it here by selecting a computer and hovering over each Qubit, through the error range bar or through Python as you seem to have done. What I've found in my experiments is that what usually ruins an experiment is the error associated with ...

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Consider https://ibm.co/joinqiskitslack the Slack link, it's always updated to a working invitation link.

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You can (and you should) always uncomputer ancilla qubits. This can be done by application of inverse gates in inverse order to original ones which prepared states of ancilla qubits. Here is an example: The purpose of the circuit is to calculate $q_0 \,\text{AND}\, q_1 \,\text{AND} q_2$. To do so, firstly $q_0 \,\text{AND}\, q_1$ is calculated and result is ...

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Just to add. If you do not have a possibility to switch control and target qubits, you can implement "upside down" CNOT with this circuit: $$(H \otimes H) CNOT (H \otimes H),$$ where $H$ is Hadamard gate and $CNOT$ is controlled NOT with control qubit upside and target qubit downside.

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I have found the solution! The problem is that each time you use the transpile function, it generates a different transpiled circuit and the order of the outcome is not necessary the same as the order of the input, so you have to use swap gates to obtain the correct one. In order to always obtain the same circuit you have to fit the seed_transpiler (as with ...

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