qecsimext is an example Python 3 package that extends qecsim with additional components.

The qecsim package is a quantum error correction simulator, which can be extended with new codes, error models and decoders that integrate into its command-line interface. This qecsimext package includes very basic examples of such components to provide a starting point for developing more sophisticated components.

Since qecsimext is intended as an example of how to develop extensions for qecsim, we will download the repository and install qecsimext in editable mode in a virtual environment. (Alternatively, you may choose to clone or fork the qecsimext repository instead of downloading it.)

• Download the repository: qecsimext-0.1b9.zip

• Install qecsimext in editable mode with developer dependencies:

$ unzip qecsimext-0.1b9.zip             # extract repo (Windows: tar -xf qecsimext-0.1b9.zip)
$ cd qecsimext-0.1b9
$ python3 --version                     # qecsimext requires Python 3.5+
Python 3.7.8
$ python3 -m venv venv                  # create virtual environment
$ source venv/bin/activate              # activate venv (Windows: venv\Scripts\activate)
(venv) $ pip install -U setuptools pip  # install / upgrade setuptools and pip
...
Successfully installed pip-21.0.1 setuptools-52.0.0
(venv) $ pip install -e .[dev]          # install qecsimext with dev tools
...
Successfully installed ... qecsimext ...
(venv) $ deactivate                     # deactivate venv
$

• Test installation:

$ source venv/bin/activate              # activate venv (Windows: venv\Scripts\activate)
(venv) $ pytest                         # run tests
...
==== 3 passed in 1.34s =====

• Run simulation example via console script:

$ source venv/bin/activate              # activate venv (Windows: venv\Scripts\activate)
(venv) $ qecsim run -r100 "ext_3qubit" "ext_3qubit.bit_flip" "ext_3qubit.lookup" 0.3
...
[{"code": "3-qubit", "decoder": "3-qubit lookup", "error_model": "3-qubit bit-flip", "error_probability": 0.3, "logical_failure_rate": 0.22, ..., "wall_time": 0.043655599000000045}]

• Run simulation example via module script with Python optimize flag:

$ source venv/bin/activate              # activate venv (Windows: venv\Scripts\activate)
(venv) $ python3 -O -m qecsim run -r100 "ext_3qubit" "ext_3qubit.bit_flip" "ext_3qubit.lookup" 0.3
...
[{"code": "3-qubit", "decoder": "3-qubit lookup", "error_model": "3-qubit bit-flip", "error_probability": 0.3, "logical_failure_rate": 0.22, ..., "wall_time": 0.03045584499999965}]

New components can be implemented and integrated into the command-line interface as described below. See also the qecsim documentation.

New codes, error models or decoders are implemented by writing classes that extend qecsim.model.StabilizerCode, qecsim.model.ErrorModel or qecsim.model.Decoder, respectively. (Fault-tolerant decoders extend qecsim.model.DecoderFTP). See ./src/qecsimext/threequbit.py for examples.

New codes, error models or decoders are integrated into the command-line interface via entries in the [options.entry-points] section of ./setup.cfg under the keys qecsim.cli.run.codes, qecsim.cli.run.error_models or qecsim.cli.run.decoders, respectively. (Fault-tolerant compatible components are under qecsim.cli.run_ftp.* keys). The format of entries is <short_name> = <module_path>:<class_name>. See ./setup.cfg for examples.

Optionally, one-line descriptions for command-line interface help messages can be provided by decorating implementation classes with qecsim.model.cli_description. See ./src/qecsimext/threequbit.py for examples.

• Since we installed qecsimext in editable mode there is no need to upgrade the installation after source code changes. However, after modifying ./setup.cfg, the qecsimext installation must be upgraded:

$ source venv/bin/activate              # activate venv (Windows: venv\Scripts\activate)
(venv) $ pip install -U -e .[dev]       # upgrade qecsimext
...
Successfully installed qecsimext

• When developing new components, qecsimext may be used as a starting point. However, if you intend to put the components in the public domain then it would be good practice to use a unique repository and root package name.

Tasks for running tests with coverage, checking style, generating documentation and building source and binary distributables can be executed using tox. See ./tox.ini for more details.

For example, distributables can be built as follows:

$ source venv/bin/activate              # activate venv (Windows: venv\Scripts\activate)
(venv) $ tox -ebuild                    # build qecsimext distributables
...
(venv) $ ls ./dist/                     # list qecsimext distributables
qecsimext-0.1b9-py3-none-any.whl    qecsimext-0.1b9.tar.gz

qecsimext is released under the BSD 3-Clause license; see LICENSE.

If you use qecsim in your research, please see the qecsim documentation for citing details.

• Source code: https://github.com/qecsim/qecsimext
• qecsim source code: https://github.com/qecsim/qecsim
• qecsim documentation: https://qecsim.github.io/
• Contact: [email protected]

Copyright 2016 - 2021, David K. Tuckett.