Developer Standalone module Setup

The Developer GUI Setup or KQCircuits Salt package sections described setting up KQCircuits for use with KLayout Editor (GUI). However, KQC can also be used without KLayout Editor by using the standalone KLayout Python module. This lets you develop and use KQCircuits completely within any Python development environment of your choice, without running KLayout GUI. For example, any debugger can then be used and automated tests can be performed. The KQCircuits elements can also be visualized using any suitable viewer or library during development.

Prerequisites

If you want to run KQCircuits outside of the KLayout Editor, you will need Python 3 and pip installed.

Successfully tested with

  • Python 3.10.14, 3.11.2

Older versions of klayout (<0.28) do not support certain new features of KQCircuits. If you want to use older klayout you may need to check out a suitable older version of KQCircuits too. API changes of klayout are backwards compatible so you are safe using older KQCircuits versions with the latest KLayout.

Installation

We recommend setting up a Python virtual environment, “venv”. This helps with containing the set of dependencies, not letting them interfere with other environments in your system.

If you have not yet done so, git clone the KQCircuits source code from https://github.com/iqm-finland/KQCircuits to a location of your choice. Same cloned local repository used for GUI developer installation (Developer GUI Setup) can be used for standalone installation.

Consider one of three types of installation.

1. Basic installation

Activate your virtual environment (if you have one) and write in command prompt / terminal:

python -m pip install -e klayout_package/python

The previous command installs only the packages which are always required when using KQC. Other packages may be required for specific purposes, see Dependency extensions. A command that installs every dependency is:

python -m pip install -e "klayout_package/python[docs,tests,notebooks,simulations,graphs]"

You can choose for which purposes you want to install the requirements by modifying the text in the square brackets. Note that there should not be any spaces within the brackets.

2. Reproducible, Secure Installation

For improved security, the dependencies can be installed such that every version of every dependency package is controlled and their hashes generated and validated. We host trusted dependency versions at klayout_package/python/requirements. If installed that way, it is also easier to troubleshoot problems since the environment will be identical to the one main developers of KQCircuits have.

Install minimum requirements of KQCircuits, subsituting <platform> with win, mac or linux:

cd klayout_package/python
python -m pip install -r requirements/<platform>/requirements.txt
python -m pip install --no-deps -e .

You can afterwards install other requirements needed for specific purposes (in this case doc and test):

python -m pip install -r requirements/<platform>/doc-requirements.txt -r requirements/<platform>/test-requirements.txt

See klayout_package/python/requirements and Dependency extensions for full list of requirements files.

3. KQCircuits exclusive python environment

If you have pip-tools installed, you can use the pip-sync command to completely rewrite you python environment to only use the pinned KQCircuits requirements, removing other packages. Only do this kind of installation on a virtual environment specifically created for using KQCircuits.

cd klayout_package/python
python -m pip install -r requirements/<platform>/pip-requirements.txt
pip-sync requirements/<platform>/requirements.txt requirements/<platform>/test-requirements.txt
python -m pip install --no-deps -e .

We first install requirements needed for pip-sync command compiled in the pip-requirements.txt file, then we run the actual pip-sync command. Since pip-sync will completely wipe out your virtual environment, you will need to know in advance which dependency extensions you will need and list them within the single pip-sync command.

Dependency extensions

We divided dependencies used by KQCircuits into following categories:

  • requirements.txt: Dependencies needed to use core KQCircuits API

  • tests, test-requirements.txt: Dependencies needed to run unit tests (see Testing) and linter. Recommended for developers of KQCircuits code.

  • docs, doc-requirements.txt: Dependencies needed to generate KQCircuits documentation, see Documentation.

  • simulations, sim-requirements.txt: Dependencies needed to export and run simulations, see Run and export in one line.

  • notebooks, notebook-requirements.txt: Dependencies needed to run Jupyter notebooks for demonstrations or for calculating needed designs.

  • graphs, graph-requirements.txt: Dependencies needed to visualise graphs, for example util/netlist_as_graph.py.

  • pip-requirements.txt: Dependencies needed for pip-tools.

  • gui-requirements.txt: Dependencies needed for KQCircuits GUI installation, used by setup_within_klayout.py and on KLayout startup. Should be targeted to the site-packages directory that the KLayout installation uses.

PyPI Installation

KQCircuits is also publicly available in the PyPI index and can be installed using:

pip install kqcircuits

You won’t be able to easily modify KQCircuits code and you won’t have access to many features such as scripts, masks, documentation and notebooks. A new Python package is automatically uploaded to PyPI for every tagged commit in GitHub.

Usage

The independence from KLayout GUI makes it possible to do all development of KQCircuits fully within a Python IDE of your choice. For example, standalone debuggers and automated testing (see Testing) can be done, which would not be possible without the standalone KLayout module.

It is possible to generate masks, run simulation scripts or even the actual simulations on the command line:

kqc mask quick_demo.py
python klayout_package/python/scripts/simulations/double_pads_sim.py -q
kqc sim waveguides_sim_compare.py -q

The output of the above commands will be in the automatically created tmp directory. If you desire the outputs elsewhere set the KQC_TMP_PATH environment variable to some other path.

The preferred way to instantiate a drawing environment in standalone mode is with the KLayoutView object:

from kqcircuits.klayout_view import KLayoutView
view = KLayoutView()

This creates the required object structure and has helper methods for inserting cells and exporting images. See the KLayoutView API documentation for more details.

Note

The user must keep a reference to the KLayoutView instance in scope, as long as references to the layout or individual cells are used.

Jupyter notebook usage

There is an example Jupyter notebook KQCircuits-Examples/notebooks/viewer.ipynb in the notebooks folder, which shows how to create and visualize KQCircuits elements with the standalone KLayout module. Run it like:

jupyter-notebook notebooks/viewer.ipynb

Updating the required dependencies

Don’t do it unless absolutely necessary! The security model (TOFU) works best if dependencies are rarely changed. When updating dependencies try to verify that the new versions are legitimate.

Edit the *requirements.in files according to your needs. Try to keep >=, <= and == version constraints to a minimum. Try to improve other dependencies too, not only the ones your need.

Compile the new requirements/<platform>/*requirements.txt files for every source *requirements.in file you changed (make sure you have pip-tools installed):

cd klayout_package/python
pip-compile --allow-unsafe --generate-hashes --upgrade --output-file=requirements/<platform>/requirements.txt requirements.in
pip-compile --allow-unsafe --generate-hashes --upgrade --output-file=requirements/<platform>/doc-requirements.txt doc-requirements.in
[...]

Substitute <platform> with win, mac or linux, and please make sure that the files will get compiled for other platforms too, not just the one you are using.

Some requirements files don’t have their corresponding *requirements.in source file. One such file is requirements/<platform>/pip-requirements.txt, which compiles requirements of pip-tool for each platform. Other requirements files are only used for CI operations.