KLayout Standalone Usage¶
The Developer Setup or Getting started (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.
If you want to run KQCircuits outside of the KLayout Editor, you will need
Python 3 and
Successfully tested with
Python 3.7.6, 3.8.5
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.
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.
This section explains how to install KQC in “development mode”, so that a link to your local KQC repo is added to the python environment. When using KQC installed in this way, the version in your local repo is thus used.
To do this, activate your python environment 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, and these can be installed by using instead a command like:
python -m pip install -e "klayout_package/python[docs,tests,notebooks,simulations]"
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.
If you do not need all KQCircuits sources but only the core KQC classes you may simply run
install kqcircuits to get the Python package only. You can use this the same way as the full
developer installation but remember that scripts, masks, documentation and notebooks are not part of
the Python package. A new Python package is automatically uploaded to PyPI for every tagged commit
kqcircuits Python package may be used with an independently downloaded KQCircuits source
directory to run tests, simulation scripts or build documentation or masks from there. You are
supposed to run most of these from the source directory or you may need to specify the
KQC_ROOT_PATH environment variable so that
kqcircuits finds the sources.
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:
python klayout_package/python/scripts/masks/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 automaticaly 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
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.
The user must keep a reference to the
KLayoutViewinstance in scope, as long as references to the layout or individual cells are used.