All Questions
36 questions
1
vote
1
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290
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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: ...
- 31
4
votes
0
answers
35
views
How does it work QasmSimulator with the option "density matrix"?
I am making some simulations on IBM Quantum Lab and as backend I tried to use QasmSimulator(method = "density_matrix") in order to simulate noise. I wanted to know how this method works in ...
1
vote
0
answers
75
views
How to perform lattice surgery with initial state $|0\rangle+|1\rangle$, with qasm?
I am trying to perform a lattice surgery. Initial state is $|0\rangle+|1\rangle$ and when I perform a smooth merge and split, I think I get $|00\rangle+|11\rangle$ but it doesn't work. Is there ...
- 41
9
votes
1
answer
5k
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What are the differences between Qiskit's AerSimulator, QasmSimulator and StatevectorSimulator?
In Qiskit, we can see the names of available simulators with the command Aer.backends(). These include:
...
- 339
3
votes
1
answer
328
views
Qiskit does not interpret qasm string as 3.0?
I am trying to get my first openqasm3.0 program and I am getting error messages that I cannot interpret.
Here is my program:
...
- 701
2
votes
1
answer
330
views
How to convert code from QISKIT to QuEST using QASM
I have been working on this project which requires a lot of qubits. Originally we have made the whole project in QISKIT as we have been using it for a long time. But the maximum number of qubits that ...
1
vote
1
answer
228
views
QASM Files on Jupyter Notebook
Is it possible to run qasm files on jupyter notebook (like with the qasm_simulator)?
I downloaded one code file and I would like to play around with it on jupyter notebook.
- 19
1
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0
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192
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How can I get the results from simulating noise models?
I'm trying to run some simulations of my quantum circuits using qasm simulator. I first tried to import the noise data from a quantum device and then use that information on qasm. Here's part of my ...
- 2,408
1
vote
2
answers
122
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Are we using the real-time error information in simulating noise on qasm?
I'm trying to run some quantum circuits on qasm simulator using the noise information from IBM Q quantum device:
...
- 2,408
3
votes
1
answer
1k
views
Simulating OpenQASM 2.0 in Qiskit?
I'm just getting started with OpenQASM, but I'm feeling a bit confused. Is there a way to run the .qasm file I've written in Qiskit (i.e. in Python), or is OpenQasm ...
- 83
1
vote
1
answer
73
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Use of Data loaders or State Initialization Circuits
I have recently started working on qiskit and I am struggling to use qc.initialize API in any practical or useful application. I have read at multiple places that ...
- 513
2
votes
1
answer
215
views
Is it true that QasmSimulator is much slower than StatevectorSimulator, or am I doing something wrong?
I'm trying to calculate the expectation value of some operator for a state that comes out of a quantum circuit using Qiskit. I was initially using ...
- 264
3
votes
1
answer
370
views
IF statement in OpenQASM2.0 on IBM Quantum Experience -- error
I have written the following toy .qasm file, which has some adaptive measurements:
...
- 166
1
vote
1
answer
561
views
How to import circuit libraries into qiskit
Im trying to put the QFT circuit in my qiskit circuit but im having trouble:
...
- 37
3
votes
1
answer
215
views
Why does running my circuit on Quantum Hardware produce such unexpected results?
I am using Jupyter Notebook with Qiskit.
I have created a program that can add two 3-bit numbers together. When I simulate this program on a qasm_simulator it works as expected and I can add any two 3-...
- 107
2
votes
3
answers
2k
views
How to read QASM files for parametrized circuits (in QISKIT)? both from_qasm_file() and from_qasm_str() fail
I am trying to work with parametrized circuits in QISKIT. I can simply create parameterized circuits, bind value(s) to parameter(s), and execute/run all instances (after binding values for parameters) ...
- 21
2
votes
3
answers
391
views
Is it possible to see the probabilities values of qubit ( alpha and beta) while measuring on IBM Quantum experience?
Is it possible to see what are the values of $\alpha$ (probability of being in state zero) and $\beta$ (probability of being in state one) while running on IBM Quantum simulator (we can call it state ...
- 55
3
votes
3
answers
284
views
Quantum Error Correction implementation in Qiskit, OpenQASM or other languages based on Python
Where can we find example(s) of implementation code in a programming language of Quantum Error Correction, whether with the standard method of measurement or the automatic method without measurement (...
1
vote
0
answers
58
views
Why do I get the error 'IBMQManagedResultDataNotAvailable'?
I'm trying to use IBMQ job manager to submit a list of quantum circuits (300 of them in total) to 'ibmq_16_melbourne'. This is what the job status looks like on IBM Quantum Experience:
I don't know ...
- 2,408
1
vote
1
answer
191
views
Is there a faster way to get 'a list of' result from 'a list of inputs'?
I had a question about obtaining the probability of a certain state from the histogram, still using this example, suppose there's a variable in my quantum circuit, it's values are stored in an 'np....
- 2,408
5
votes
1
answer
1k
views
How to run a OpenQASM 3.0 file?
When uploading a QASM-file with ÒPENQASM 3.0; as first line, the code editor on quantum-computing.ibm.com will throw an error.
However the qiskit Python library ...
0
votes
1
answer
152
views
Odd behavior with Qiskit Pauli operators
I was creating a simple implementation of the Hadamard test when I came across the following, what seems like, strange behavior.
Consider the following snippet, which is part of the computating the ...
- 334
0
votes
1
answer
597
views
Qiskit implementation for MPS
Now, I'm implementing Matrix product state method with QasmSimulation in Qiskit.
following code
The problem arise when I set number of qubits. When running it with 27qubits is very fast
but, for 24, ...
- 967
2
votes
1
answer
188
views
Why running time of qasm simulator is significantly smaller in comparison with quantum machines?
I ran a 3-qubit measurement circuit on QASM simulator as well as on IBM Q Melbourne, Santiago and Vigo machines. The running time on the simulator is in few milliseconds (400-800) while in the case of ...
- 305
4
votes
1
answer
1k
views
Is there any way we get the state vector/density matrix of a noisy simulation in qiskit?
In Qiskit we can't use noise models in the 'state vector_simulator' or the 'unitary simulator', hence making it impossible to compute fidelity of the output of the noisy circuit and the noiseless ...
4
votes
0
answers
62
views
What is the executable opcode for Qiskit quantum hardware, as the quantum circuits or the transpiled/compiled QObj/ QASMQObj are assembly languages? [duplicate]
When we write a QASM code or build quantum circuit on Qiskit GUI, it converts it into QObj/QASMQObj (refering paper Qiskit Backend Specifications for OpenQASM and OpenPulse Experiments) or its ...
1
vote
1
answer
144
views
Is there a standard way to save pulse schedules akin to a qasm for a circuit?
If I create a QuantumCircuit, I can save all the information necessary to reconstruct the circuit using the qasm method. In addition, these qasm strings can be sent directly to the IBM quantum ...
- 45
1
vote
1
answer
1k
views
How can I install the 'ibmq_qasm_simulator' backend?
I'm having trouble running the following cell:
The system told me "The 'ibmq_qasm_simulator' backend is not installed in your system." I'm so confused. Is there a way I can install this backend in my ...
- 2,408
2
votes
1
answer
814
views
How can I use IF gate in IBM Q composer?
I just want to use the "if" gate in IBM QX circuit composer, but I don't know how.
- 21
1
vote
1
answer
443
views
OPENQASM: How to include my own libraries
I studied the OPENQASM 2.0 spec a few times but failed to find a way to include my own libraries. Have I missed anything?
Right now, the only way is to use ...
- 123
5
votes
1
answer
418
views
How to see the QASM code corresponding to compiled Q# function?
I'm learning Q#. Is there any way to see the QASM code of a Q# function I write, the same way I can see the disassembly of a C# function?
- 153
2
votes
1
answer
922
views
How to define custom controlled unitaries in OPENQASM 2.0?
According to the OPENQASM 2.0 documentation, it's possible to define custom unitary gates using the format:
gate name(params) qargs
{
body
}
where the optional ...
- 17.8k
1
vote
0
answers
74
views
QE error: No handlers could be found for logger
When I run a QASM program on a QE simulator, I get this error.
No handlers could be found for logger
"IBMQuantumExperience.IBMQuantumExperience"
What ...
- 11
2
votes
1
answer
310
views
Print circuit compiled on hardware?
I would like to see the compiled circuit as executed on a hardware.
Nominally, this sequence of commands should return the QASM circuit in the variable ran_qc, but ...
- 59
2
votes
1
answer
573
views
How to make "random U3" in QASM?
I want to make an operator:
$\mathrm{U3}(\arccos(\sqrt p),0,0)$, when $p$ is a random value between $0$ and $1$
How do I write code in QASM language of this "random $\mathrm{U3}$" operator?
8
votes
2
answers
692
views
Construct Controlled-$G^{\dagger}$ from known Controlled-$G$
Let there be a known a scheme (quantum circuit) of Controlled-G, where unitary gate G has G$^†$ such that G≠G$^†$ and GG$^†$=I (for example S and S$^†$, T and T$^†$, V and V$^†$, but not Pauli and H ...
