This repository contains the Python tutorials and implementations available at https://pennylane.ai/qml. Content includes:

• Key concepts of QML. Explore and understand the key concepts underpinning variational quantum circuits and quantum machine learning.

• Beginner tutorials. Tutorials introduce core QML concepts, including quantum nodes, optimization, and devices, via easy-to-follow examples.

• Implementations of cutting-edge QML research. Take a deeper dive into quantum machine learning by exploring cutting-edge algorithms on near-term quantum hardware.

You can contribute by submitting a tutorial or a demonstration of a recent quantum machine learning paper/result.

• Tutorials and demonstrations are written in the form of an executable Python script. Any package listed in requirements.txt you can assume is available to be imported. Matplotlib plots will be automatically rendered and displayed on the QML website.

  Note: try and keep execution time of your script to within 10 minutes.

• If you would like to write the tutorial using a Jupyter notebook, you can convert the notebook to the required executable Python format by using this script.

• All tutorials/implementations should have a file name beginning with tutorial_. Beginner tutorials go in the beginner directory, while implementations go in the implementations directory.

• Restructured Text sections may be anywhere within the script by beginning the comment with 79 hashes (#). These are useful for breaking up large code-blocks.

• You may add figures within ReST comments by using the following syntax:

  ##############################################################################
  #.. figure:: ../<tutorial type>/<tutorial name>/image.png
  #    :align: center
  #    :width: 90%

  where <tutorial type> is one of beginner or implementation (depending on what content you submitting), and <tutorial name> is a sub-directory with the name of your tutorial.

• When complete, create a gallery link to your tutorial/implementation, by adding the following to either beginner.rst or implementations.rst:

  .. customgalleryitem::
      :tooltip: An extended description of the tutorial/implementation
      :figure: <tutorial type>/<tutorial name>/thumbnail.png
      :description: :doc:`<build location>/pytorch_noise`

  Here, <build_location> is either tutorial (for beginner tutorials), or app (for implementations).

  You should also add a link to your tutorial to the table of contents, by adding to the end of the .. toctree::.

• Finally, run your script through the Black Python formatter,

  pip install black
  black -l 100 tutorial_new.py

  and you are ready to submit a pull request!

While you are free to be as creative as you like with your tutorial or implementation, there are a couple of guidelines to keep in mind.

• Submissions should include your name (and optionally email) at the top under the title.

• All contributions must be made under the Apache 2.0 license.

• The title should be clear and concise, and if an implementation, be similar to the paper that is being implemented.

• All tutorials/implementations should include a summary below the title. The summary should be 1-3 sentences that makes clear the goal and outcome of the tutorial, and links to any papers/resources used.

• Code should be clearly commented and explained, either as a ReST-formatted comment or a standard Python comment.

• Thumbnails should be legible, interesting, and unique --- but not too busy! Any included text should be minimal and legible

• If your content contains random variables/outputs, a fixed seed should be set for reproducibility.

• All content must be original or free to reuse subject to license compatibility. For example, if you are implementing someone elses research, reach out first to recieve permission to reproduce exact figures. Otherwise, avoid direct screenshots from papers, and instead refer to figures in the paper within the text.

• All submissions must pass code review before being merged into the repository.

To build the website locally, simply run make html. The rendered HTML files will now be available in _build/html. Open _build/html/index.html to browse the built site locally.

Note that the above command may take some time, as all tutorials and implementations will be executed and built! Once built, only modified tutorials will be re-executed/re-built.

Alternatively, you may run make html-norun to build the website without executing tutorials/implementations.

• Source Code: https://github.com/XanaduAI/QML
• Issue Tracker: https://github.com/XanaduAI/QML/issues

If you are having issues, please let us know by posting the issue on our GitHub issue tracker.

We are committed to providing a friendly, safe, and welcoming environment for all. Please read and respect the Code of Conduct.

The materials, tutorials, and implementations in this repository are free and open source, released under the Apache License, Version 2.0.

The file custom_directives.py is available under the BSD 3-Clause License with Copyright (c) 2017, Pytorch contributors.