Importer for parsing OpenQASM 3 strings into Qiskit circuits
Project description
Importer from OpenQASM 3 to Qiskit
This repository provides the Python package qiskit_qasm3_import
, which is a
basic and temporary importer from OpenQASM 3 into Qiskit's QuantumCircuit
.
Qiskit itself accepts this package as an optional dependency if it is installed.
In that case, Qiskit exposes the functions qiskit.qasm3.load
and
qiskit.qasm3.loads
, which are wrappers around qiskit_qasm3_import.parse
.
This project is a stop-gap measure until various technical decisions can be
resolved the correct way; Terra makes strong guarantees of stability and support
in its interfaces, and we are not yet ready to make that commitment for this
project, hence the minimal wrappers.
Example
The principal entry point to the package is the top-level parse
function,
which accepts a string containing a complete OpenQASM 3 programme. This complex
example shows a lot of the capabilities of the importer.
OPENQASM 3.0;
// The 'stdgates.inc' include is supported, and the gates are only available
// if it has correctly been included.
include "stdgates.inc";
// Parametrised inputs are supported.
input float[64] a;
qubit[3] q;
bit[2] mid;
bit[3] out;
// Aliasing and re-aliasing are supported.
let aliased = q[0:1];
// Parametrised gates that make use of the stdlib.
gate my_gate(a) c, t {
gphase(a / 2);
ry(a) c;
cx c, t;
}
// Gate modifiers work as well; this gate is equivalent to `p(-a) c;`.
gate my_phase(a) c {
ctrl @ inv @ gphase(a) c;
}
// We handle mathematical expressions on gate creation and complex indexing
// of temporary collections.
my_gate(a * 2) aliased[0], q[{1, 2}][0];
measure q[0] -> mid[0];
measure q[1] -> mid[1];
while (mid == "00") {
reset q[0];
reset q[1];
my_gate(a) q[0], q[1];
// We support the builtin mathematical symbols.
my_phase(a - pi/2) q[1];
mid[0] = measure q[0];
mid[1] = measure q[1];
}
// The condition resolver can also handle simple cases that don't look
// _exactly_ like equality conditions.
if (mid[0]) {
// There is limited support for aliasing within nested scopes.
let inner_alias = q[{0, 1}];
reset inner_alias;
}
out = measure q;
Assuming this program is stored as a string in a variable program
, we then
import it into a QuantumCircuit
by doing:
from qiskit_qasm3_import import parse
circuit = parse(program)
circuit
is now a complete QuantumCircuit
, so we can see exactly what it
turned into:
circuit.draw()
┌───────────────┐┌─┐ ┌─────────────┐┌──────────┐┌─┐
q_0: ┤0 ├┤M├───┤0 ├┤0 ├┤M├───
│ my_gate(2*a) │└╥┘┌─┐│ ││ │└╥┘┌─┐
q_1: ┤1 ├─╫─┤M├┤1 ├┤1 ├─╫─┤M├
└──────┬─┬──────┘ ║ └╥┘│ ││ If_else │ ║ └╥┘
q_2: ───────┤M├────────╫──╫─┤ While_loop ├┤ ├─╫──╫─
└╥┘ ║ ║ │ ││ │ ║ ║
mid_0: ════════╬═════════╩══╬═╡1 ╞╡0 ╞═╬══╬═
║ ║ │ │└──────────┘ ║ ║
mid_1: ════════╬════════════╩═╡0 ╞═════════════╬══╬═
║ └─────────────┘ ║ ║
out_0: ════════╬══════════════════════════════════════════╩══╬═
║ ║
out_1: ════════╬═════════════════════════════════════════════╩═
║
out_2: ════════╩═══════════════════════════════════════════════
Installation
Install the latest release of the qiskit_qasm3_import
package from pip:
pip install qiskit_qasm3_import
This will automatically install all the dependencies as well (an OpenQASM 3 parser, for example) if they are not already installed. Alternatively, you can install Qiskit Terra directly with this package as an optional dependency by doing
pip install qiskit-terra[qasm3-import]
Developing
If you're looking to contribute to this project, please first read our contributing guidelines.
Set up your development environment by installing the development requirements with pip:
pip install -r requirements-dev.txt tox
This installs a few more packages than the dependencies of the package at
runtime, because there are some tools we use for testing also included, such as
tox
and pytest
.
After the development requirements are installed, you can install an editable version of the package with
pip install -e .
After this, any changes you make to the library code will immediately be present when you open a new Python interpreter session.
Building documentation
After the development requirements have been installed, the command
tox -e docs
will build the HTML documentation, and place it in docs/_build/html
. The
documentation state of the main
branch of this repository is published to
https://qiskit.github.io/qiskit-qasm3-import.
Code style and linting
The Python components of this repository are formatted using black
. You can
run this on the required files by running
tox -e black
The full lint suite can be run with
tox -e lint
License
This project is licensed under version 2.0 of the Apache License.
Project details
Download files
Download the file for your platform. If you're not sure which to choose, learn more about installing packages.
Source Distribution
Built Distribution
Hashes for qiskit_qasm3_import-0.5.0.tar.gz
Algorithm | Hash digest | |
---|---|---|
SHA256 | d8d39ac176eaa7f2414dab897ff449ea1e5d854230b262b21724d138939a6476 |
|
MD5 | 2e369af2b4f34552e0748d5ae87a264b |
|
BLAKE2b-256 | 6940e6ea9dc59d50bbf5ca61e695cd986ded1386ab65f6bfb0181144555d7c1f |
Hashes for qiskit_qasm3_import-0.5.0-py3-none-any.whl
Algorithm | Hash digest | |
---|---|---|
SHA256 | 137f98e870160dc274eb920603c1c0032f2534b5e365b0243e57b25dfee46f61 |
|
MD5 | 0fac377154833bbd2e874f9f935ef6be |
|
BLAKE2b-256 | cd1d12529a4ab9910ab15409ac79fff32a729cf54d65187b386954a52fd84f2b |