Questions tagged [qasm]
Quantum assembly language (QASM) called OpenQASM is used to implement experiments with low depth quantum circuits. OpenQASM represents universal physical circuits over the CNOT plus SU(2) basis with straight-line code that includes measurement, reset, fast feedback, and gate subroutines. The simple text language can be written by hand or by higher level tools and may be executed on the IBM Q Experience. (arXiv:1707.03429)
69
questions
4
votes
0
answers
47
views
Are there tools I can use to test OpenQASM 3 circuits?
I recently added a to_qasm method to stim. An issue I'm having is how to test that the outputs are correct. I can test OpenQASM 2 outputs by giving the output to ...
- 33.3k
1
vote
1
answer
54
views
Limited qubit number available in Aer Statevector simulator
I tried to run a calculation of 37 qubits with a Statevector simulator on Qiskit. The following is a demo code.
...
- 107
1
vote
1
answer
96
views
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
1
vote
1
answer
63
views
New QASM2ParseError for old circuit on IBM composer
A while ago I wrote an example of quantum teleportation circuit in the IBM Composer which ran fine as of three days ago. Yesterday, however, when I try to run the circuit, I get the following error:
...
0
votes
0
answers
32
views
How to augment a QASM circuit for orbital rotation
Could anyone advise on how to properly augment the hamiltonian circuits in https://github.com/CQCL/ethz-hackathon22/tree/main/benchmarking/circuits for orbital rotation ? https://poe.com/s/...
- 7
2
votes
2
answers
290
views
How to get QASM code from an Amazon Braket circuit in Python?
As an example, consider the following Circuit defined by using the Python amazon-braket-sdk:
...
- 1,422
2
votes
1
answer
743
views
Convert from QASM code to Qiskit Code
I'm looking for something that performs a conversion such as qiskit.circuit.QuantumCircuit.qasm, but for qasm code. In other words, a means to convert qasm code to ...
- 21
1
vote
2
answers
239
views
Is there any method to parse a qasm in qiskit
I'd want to parse the qasm file for analyze the quantum gate consisting its qasm file.
However, Qiskit provides the attribute of the quantum circuit, ...
1
vote
2
answers
93
views
How to simplify sequence of gates in QASM file?
I would like to know if there is a functionality in qiskit to simplify a sequence of gates in a QASM file. For example, say we have a sequence of two expensive (in fault-tolerant context) gates $TT$. ...
- 2,359
1
vote
2
answers
200
views
Conversion error: from a QISKIT circuit to a QASM string and back
I created a circuit in qiskit and then converted it into a QASM string. When I try to make a circuit out of the QASM string I get the error:
...
- 2,359
2
votes
1
answer
191
views
OpenQASM circuits in Stim
I would like to run circuits saved as OpenQASM circuits in Stim. Does anyone know how to import these circuits from OpenQASM to Stim?
Many thanks.
- 55
4
votes
0
answers
34
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 ...
3
votes
1
answer
172
views
I would like to use Open QASM 3 what if any backends can I use to?
From my limited understanding Azure Quantum and IBM Qiskit backends do not support OpenQASM 3. However, Amazon Braket does support a subset of Open QASM 3 (proof). What is the best way/backend to test ...
- 31
4
votes
1
answer
204
views
Does Qiskit allow for QASM 3.0 code to be utilized?
I am interested in using QASM 3.0 after reading it's documentation and seeing it's examples 1. However, I see that in IBM Quantum Experience QASM 3.0 is not supported yet. Is there any way I can run ...
- 41
1
vote
3
answers
709
views
What are the differences in using qasm, statevector, and unitary simulators in qiskit?
From my understanding statevector is a more simplistic using vector space, qasm is supposed to introduce noise like running it on an actual quantum computer. What types of problems would you use one ...
- 37
2
votes
0
answers
230
views
Does Qasm Simulator add noise by default?
I am wondering if Qiskit QasmSimulator adds noise by default or not. I am asking because I have 2 circuits:
circuit 1: computes cosine similarity between two vectors
circuit 2: computes cosine ...
- 105
1
vote
0
answers
70
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 ...
- 21
9
votes
1
answer
3k
views
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
6
votes
1
answer
1k
views
Where is definitive documentation for OpenQASM 2.0 and 3.0
I have gotten conflicting information about OpenQASM; some sources point to version 3 while others say 3 is not ready. I want to refer to a document that will tell me what instructions actually work ...
- 703
3
votes
1
answer
269
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:
...
- 703
2
votes
1
answer
251
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
174
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
vote
0
answers
140
views
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 ...
- 2,378
1
vote
2
answers
101
views
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:
...
- 2,378
3
votes
1
answer
869
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
0
votes
1
answer
202
views
How to build and visualize circuit from matrix?
In paper Efficient quantum algorithm for solving travelling salesman problem: An IBM quantum experience, the authors use gate $U_j$ and its decomposition
$$
U_j =
\begin{pmatrix}
\mathrm{e}^{ia} &...
- 129
1
vote
1
answer
59
views
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 ...
- 391
2
votes
1
answer
198
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 ...
- 254
3
votes
1
answer
278
views
IF statement in OpenQASM2.0 on IBM Quantum Experience -- error
I have written the following toy .qasm file, which has some adaptive measurements:
...
- 156
3
votes
1
answer
318
views
Is there a way to within a quantum circuit work out if a qubit is in a superposition or not?
Preferably using the gates found in QASM/Qiskit and the qubit stays in the superposition and no measurement is made, i.e. the output of if it is in a superposition or not is a binary answer in another ...
- 45
1
vote
1
answer
335
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
166
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-...
- 97
2
votes
1
answer
1k
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
318
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 ...
- 57
3
votes
3
answers
213
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 (...
2
votes
1
answer
122
views
Is it possible to modify pulse schedules in QASM?
Is it possible to modify a pulse schedule of a circuit compiled using QASM? I know this is possible using OpenPulse, but it seems none of the IBM backends support OpenPulse. So is it possible to do ...
- 21
1
vote
0
answers
47
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 ...
- 2,378
1
vote
1
answer
137
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....
- 2,378
5
votes
1
answer
918
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
139
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 ...
- 324
0
votes
1
answer
372
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, ...
- 877
2
votes
1
answer
163
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
1
vote
0
answers
69
views
What causes the random variations in the probabilities with respect to the theoretical values, in IBM and QASM simulators?
When I measure 2 and 3 qubits after putting H gate on all of them, there is a variation in probabilities of results in comparison with theoretical values (25% and 12.5%, respectively).
This occurs on ...
- 305
0
votes
2
answers
701
views
How to plot histogram using statevector simulator?
I'm trying to run my quantum circuit and plot the simulation result (counts) using the statevector simulator (to avoid 'shot noise'). However, instead of a 2-d histogram, the examples on Qiskit ...
- 2,378
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
119
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
2
votes
0
answers
122
views
Post-selection in QASM
In some quantum algorithms (for example HHL or quantum machine learning algorithms) an ancilla qubit(s) is measured firstly and based on result of the measurement other qubit(s) are measured or not. ...
- 13.6k
1
vote
1
answer
123
views
Problem with comments and code rearranging in IBM Q web interface
I wrote some code in QASM in the IBM Q Experience web interface and then I added some comments. After that I saved the code and run it. However, the code was rearranged (for example some gates were ...
- 13.6k
1
vote
1
answer
907
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 ...
- 2,378