Questions tagged [programming]
For any questions whose answer is expected to require code or programming notions. For questions about a specific framework (e.g. qiskit or cirq) please also include a more specific tag. If your question is about installation or any specific framework error, consider posting it in https://stackoverflow.com/ instead.
1,521
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Are there libraries based on qiskit that can trace over unentangled qubits?
Suppose I have a QuantumCircuit object qc, which contains some unentangled qubits, and a Hamiltonian whose expectation value I ...
2
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Create a superposition among the basis states of G for the hidden subgroup problem, implementing $\frac{1}{\sqrt{|G|}}\sum_{g\in G} | g,0\rangle$
I’ve been studying Simon’s problem and developing simulation models using Mathematica to extend the problem to other abelian groups and hidden subgroups of order $\geq 2$. I can now obtain the $h^\...
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Simulator able to run SwitchCase in qiskit?
I am trying to run my circuit which is the following on a simulator. However, when I want to execute this on almost all the simulators the following error pops up:
"The control-flow construct '...
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Is there a publicly available compiler for OpenQasm3?
Today (Nov 2023) using OpenQasm3 in the IBM ecosystem can only be done by exporting OpenQasm3 programs to python QuantumCircuit object via qiskit.qasm3.load and qiskit.qasm3.loads or by exporting ...
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94
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If_test() - Dynamic Circuits in qiskit
I am trying to run a dynamic circuit by having mid-measurement in my code as follows:
...
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66
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How to explain the output as $|-\rangle$
I am a complete newbie to quantum computing and qiskit. I am trying to implement $H$ gate in Measurement-Based QC architecture based on a paper "Qiskit As a Simulation Platform for
Measurement-...
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1
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How to measure in $\sigma_x$ basis in Qiskit? [duplicate]
As we know, Qiskit can give us the results of our measurements in computational or, better to say, $\sigma_z$ basis. However, I am courageous about measuring the qubit in, for instance, $\sigma_x$ ...
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Phase shift on qiskit quantum teleportation simulation
I wonder in Qiskit why the phase shift occurred in my simulation and how I can turn it off.
I posted another question regarding the same simulation here, and while I tried to solve this on my own, I ...
2
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1
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56
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Consecutive phased X rotation gates simplification
I have two consecutive phased X rotation (see cirq PhasedXPowGate gate definition), how to find both t' and p' angles (according to previoux cirq definition) so that two consecutive PhasedXPowGate are ...
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Is there a way to implement a noisy CNOT gate using CUGate in Qiskit
Wondering if there's a way to implement the noisy version of CNOT (or CX) gate via CUGate using qiskit library for a given fidelity p?
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Converting a dictionary to a statevector in Qiskit
Suppose we have a dictionary of computational basis states and their amplitudes:
{'01':0.5, '10':0.5, '11':0.5, '00':0.5}
How do I convert this (or any arbitrary ...
- 325
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Quantum Lookup Table circuit
I am trying to use the paper "A Realizable GAS-based Quantum Algorithm for Traveling Salesman Problem (2022)". However, it never explains how the index converter works, beyond it being a ...
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66
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Single-shot error correction for the surface code with measurement errors
I am trying to implement a single-shot error correction for the surface code with data + measurement errors (both with prob. p), using the (build-in) BP+OSD decoder. I am mostly following these papers:...
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How to discard one of the states in a product state in qiskit?
Suppose I have a state in qiskit which is a product of states, for example:
$| \psi \rangle = \left(\frac{ \sqrt{2} | 000 \rangle + |111 \rangle} {\sqrt 3}\right) \...
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How to use parameters in QuTiP?
I am working with QuTiP to do some calculations based on my proposed Hamiltonian. The Hamiltonian of my system has some coupling constants that show the strength of coupling between matter and light(...
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Set the initial state of the QuantumCircuit using the Statevector object
Suppose we have a 4-qubit quantum state state which is a Statevector object:
...
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56
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Is it possible to simulate a quantum algorithm on a classical computer? [duplicate]
I am designing a quantum algorithm that I would like to simulate and test, but I need to be able to simulate it on a classical computer.
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How can I pass multiple embeddings in my function?
I have a problem with my code. I would like to try multiple embeddings in my kernel (I'm using the adjoint method). My idea is to pass them to the function and use them depending on what I pass. ...
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How to collapse the subcircuits in a QuantumCircuit?
Suppose I have a QuantumCircuit object named FC, which explicitly contains the identity gate, and convert it into a gate using <...
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How to create a 3-D state (array) of qubits in qiskit or cirq etc?
I want a 3-D cube-like array for state of qubits, on which I want further to implement different sets of rotations, etc, for cryptographic means. You can create a 2D grid qubit in cirq with ...
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Error: module 'rustworkx' has no attribute 'visit' when trying to execute a quantum circuit in a real quantum computer from IBM
I am trying to use a real quantum computer from IBM. I have the next code:
...
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1
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25
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DeprecationWarning: Back-references to from Bit instances to their containing Registers have been deprecated
I have the following code
for instruction, qargs, cargs in qc.data:
qbit: qiskit.circuit.Qubit = qargs[0]
print(qbit.register)
print(qbit.index)
the ...
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0
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34
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Is there a Qutip equivalent of "expand_operator" for superoperators?
I want to calculate a superoperator for a small noisy subsystem consisting of $k$ qubits, and expand it to $n > k$ qubits, where the remaining $n-k$ qubits are not subject to any noise. ...
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63
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SLSQP optimizer(scipy.minimize) doesn't update parameters
I'm trying to find optimal parameters that minimize the cost functions.
In cost function, it calculates the classical-fisher-information at a certain point(phi[0] = np.pi).
Cost-function takes 3-...
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Can D-Wave presently solve real-world problems that conventional computers cannot solve?
There are number of threads on this site about the ability of QCs solving real-world problems (see for example What are the practical applications of quantum computing in engineering by the year 2030?,...
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Is there any programming project that implements one quantum error correction code or demonstrates it?
A gigantic list of all the error correction codes(Classical Domain, Quantum Domain, Classical-quantum Domain), see https://errorcorrectionzoo.org/all
There are lots of quantum error correction code. ...
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102
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Create qnode with density matrix on pennylane
I'm using pennylane.
What I want to do is
Create a qnode with the 2*2 density matrix of a single qubit one. It has the parameter as phi
Given density matrix:
$$\...
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1
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101
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Design a full adder to add two 4-bits integer and measuring on 4 quantum states
I am trying to implement a full adder with minimum of 8 qubits to add two 4 bit integers. Integer 1 will be added on q[0-3] while integer 2 will be added on q[4-7]. The output will be measured on q[0-...
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194
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Cannot import tensorflow_quantum module in Colab
I was trying to install the tensor flow quantum module using the one given in their official website but it is showing these errors while installing.
...
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1
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112
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Problems trying to plot the classical Fisher information with Pennylane
I'm working with pennylane. My goal is to plot CFI(Classical Fisher Information)with following quantum state.
With the above equation I set gamma as 0. Then It becomes:
If gamma is not equal to zero,...
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55
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Python code for D-Wave Annealer
In the below screenshot, I am aware of resolving the issue by reducing num_reads as the annealing time is exceeding my allowance. Although it works, my question ...
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If Statement OpenQasm 2.0
in the documentation for OpenQasm 2.0 it says one can use an if statement like so:
if(c_reg==int) Quantum Operation.
However, I would like to execute the following: ...
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2
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1
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233
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New mode of Quantum and - or gate
I’m Aurelio, a computer engeneering student and I would propose a new quantum gate that maybe could be interesting to implement and use. I don’t know if such idea is already known but I have not found ...
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2
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How do I find out which packages of qiskit are compatible with eachother?
In particular I try to find out which version of qiskit is compatible with which version of qiskit-ibm-runtime. In my setup ...
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104
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Drawing circuit in pennylane
I am trying to draw the circuit in pennylane but even after my hours of trying I am completely unsuccessful.
Below is my code. Any little guidance of yours can help me a lot.
...
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Qiskit spends a lot of time on method acquire of thread.lock objects
I am trying to run VQE algorithm with Qiskit, using the following code:
...
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How to add a value of -1/2 on the amplitude of a quantum state?
I have a quantum state which is in
$ \cos(c*f(x) + \pi/4) |0\rangle + \sin(c*f(x) + \pi/4) |1\rangle$
by using bunch of RY gates. Now I want to measure the probability of getting the state at $|1\...
2
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1
answer
51
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What are the theoretical minimum times for quantum and classical logic gates?
I'm interested in better understanding the ultimate limits on how fast quantum and classical logic gates can be performed. Based on principles like the time-energy uncertainty relationship, there ...
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126
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Cannot Download TensorFlow Quantum
Hey Quantum Computing community,
I cannot get TensorFlow Quantum to work even though I am using
pip install tensorflow-quantum
I have TensorFlow already on Visual ...
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3
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200
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0
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1
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Displaying the circuit diagram associated to a circuit in Q#+Python
I am learning the Q# language, and my script is in Python (I am using the online Azure interface).
I created an example quantum circuit on three qubits:
...
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Does subtraction circuit have a class like full or half Carry adder circuit in qiskit? one subtraction circuit code-example in qiskit?
I need a subtraction circuit to calculate Laplacian in edge processing, but I didn't find any class in qiskit.Do I have to write the code myself?
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Converting Qubits to +-1/2 Spin System for Expectation Value Calculation
I have a quantum system that consists of spin states with eigenvalues of +-1/2. However, in quantum computing, qubits are typically represented as states |0⟩ and |1⟩. I want to calculate the ...
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293
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ImportError qiskit_ibm_runtime
When I try to import qiskit_ibm_runtime I get the following error:
...
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91
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Eigenstates differ between Qutip and Quspin
I am currently trying to adapt a code working well with Qutip to Quspin to optimize it.
I managed to create what I believe are the same systems with both libraries, but I don't get the same ...
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Tf.einsum vs matmul for computing density matrix from a set of Cholesky decomposed matrices
I am trying to construct a density matrix of shape 256x256 from a set of T matrices. These T matrices are all Cholesky-decomposed matrices. But I am not sure if the ...
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Ensemble classification with Rigetti and Qiskit devices : Params.npy
I want ask how the params.npy variable were obtained? It would be great if you provide the codes for my better understanding.
...
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Implementing time evolution gate for density matrix in PennyLane circuit
I am trying to create a circuit which time evolves a density matrix $\hat{\rho}$ with the parameterized Hamiltonian
$$\hat{H}(\theta) = e^{(-i \sum_m \theta_m \Lambda_m)}\hat{H}_ce^{(i \sum_m \theta_m ...
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What is an initial state of a qubit in PennyLane?
I just started trying to use the PennyLane Python package. It seems like the default.qubit device initializes each wire as an up-spin qubit. However, I am not ...
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