Convert math content: a plugin for Pelican, an extension for Markdown

Extension for Python-Markdown to convert math tags to math scripts, plus a plugin for the Pelican static site generator.

Usage

1. Install package.
2. For Pelican: set up KaTeX header.
3. For Pelican (optionally): set up shortcuts for your favorite symbols or macros.
4. For Pelican: define latex: true at the header of each article that should include KaTeX.
5. Write an inline math tag either by:
   • enclosing text between \( and \), e.g. \(foo _bar_ baz\), or
   • between two $ symbols if the text contains no space, e.g. $a_b^c$.
6. Write a display math block by surrounding an entire paragraph either with '[' and \], or with two $$ tags. Example:

\[
    % For a visual proof, see https://link.springer.com/article/10.1007/s00283-018-9816-4
    \pi ^ e < e ^ \pi
\]

Inline math tags will then be converted to <script type="math/tex"> bar _baz_ qux </script> during site generation, and display blocks to:

<script type="math/tex; mode=display">% <![CDATA[
    % For a visual proof, see https://link.springer.com/article/10.1007/s00283-018-9816-4
    \pi ^ e < e ^ \pi %]]></script>

These are then rendered with KaTeX in the browser.

Installation

For the Pelican plugin, you just need to install the package:

python -m pip install git+https://github.com/treszkai/pelican-md-math.git

For Markdown usage, you also need to specify the path or instance of the extension:

import markdown
md = markdown.Markdown(extensions=['pelican.plugins.md_math'])

or

import markdown
from pelican.plugins.md_math import MathExtension

md = markdown.Markdown(extensions=[MathExtension()])

Setting up KaTeX headers for Pelican

Two steps are required:

• Copy the supplied katex.html file to your theme's templates directory.
• Modify the necessary templates (e.g. article.html for the article pages) with adding the following in the {% block head %} block, before the {% endblock %} tag. (An example article.html is supplied, but you should use the one that comes with your theme.)

  {% if (article.latex is defined and article.latex) or article.latex_macros is defined %}
    {% include 'katex.html' %}
  {% endif %}

If your repository doesn’t contain a copy of your theme, then just create a directory templates with the two files mentioned above, and set THEME_TEMPLATES_OVERRIDES = ['templates'] in your pelicanconf.py.

Adding LaTeX macros for Pelican

Site-level macros

Define a LATEX_MACROS dictionary in pelicanconf.py:

LATEX_MACROS = {
    r'\RR': r'\mathbb{R}',
    r'\EE': r'\mathbb{E}',
    r'\indep': r'\perp\!\!\!\perp',
    r'\emptyset': r'\varnothing',
    r'\Godel': r'\ulcorner #1 \urcorner',
}

These can be used as ordinary LaTeX macros, e.g. \RR or \Godel{\phi}. The latter example demonstrates a parametric macro.

Article-level macros

You can define latex_macros in the article header as follows:

latex: true
latex_macros:
    "\D": "\mathcal{D}"
    "\N": "\mathcal{N}"
    "\Godel": "\ulcorner #1 \urcorner"

(In the presence of latex_macros, you don't need the latex: true line.)

Known limitations

• Doesn’t create a display block if it contains an empty line
• Doesn’t ignore an escaping backslash before the \( or $ tags.
• ]]> in the math input will probably mess up the HTML output.
• All files are parsed, regardless of whether LaTeX is enabled for the article.

Contributing

If you find an issue in this extension, please open an issue or a pull request.

You can always [contribute to Pelican]: https://docs.getpelican.com/en/latest/contribute.html