=====================
Writing documentation
=====================

This is a short tutorial on how to contribute to the documentation of ``bilby``.

Writing the basics
------------------

First, open your terminal and head to the ``docs`` directory in your clone of
`bilby`. Once here, you'll notice there are a number of `*txt` files. Each one
is a page of the documentation.

Let's say you want to write documentation about the your new feature (or update
the existing documentation). Simply open a new file ``a-new-feature.txt`` in
your text editor. Then add a title and some text::

   ====================
   A new bilby feature!
   ====================

   Here we'll put a description of the new feature

Next, in order to get your new page known by the rest of the documentation,
open ``index.rst`` and, under ``toctree`` add the name of your file (without
the suffix). For the example above::

   .. toctree::
      :maxdepth: 3
      :caption: Contents:

      likelihood
      samplers
      writing-documentation
      a-new-feature


Checking the results
--------------------

You can check what this will look like by (whilst in the ``docs`` directory)
running the command::

   $ make html

This will create a directory ``./_build/html`` with the documentation. To
see the result, open the file ``./_build/html/index.html`` in your browser.


Pushing your changes to master
------------------------------

To contribute your documentation changes, you should create a branch and add in
all of the new/changed files::

   $ git checkout -b adding-my-new-documentation
   $ git add index.txt
   $ git add a-new-feature.txt
   $ git commit -m "Adding my documentation for the feature"
   $ git push origin adding-my-new-documentation

Then, on the web interface create a merge request.

Using reStructured text
-----------------------

The help files are written in reStructured text format. To familiarise yourself
with these features visit http://www.sphinx-doc.org/en/master/usage/restructuredtext/basics.html.

A useful feature is the ability to `format code examples <http://www.sphinx-doc.org/en/stable/markup/code.html>`_. This is done through the use of ``::`` and indendentation. For
example, to make this code block::

   import bilby

You would write::

   to make this code block::

      import bilby

reStructured text is very powerful, but can be quite particular. For example,
**all code blocks must be indented by 3 spaces**.

Sphinx autosummary
------------------

Most of the documentation for ``bilby`` should be written in the `docstrings
<https://www.python.org/dev/peps/pep-0257/>`_ of the functions/classes themselves. We
can add these into the online documentation using `autosummary
<https://www.sphinx-doc.org/en/master/usage/extensions/autosummary.html>`_.
New code should automatically be added to the API tree.

