Contributing to the documentation¶
Contributing to the documentation benefits everyone who uses pandas. We encourage you to help us improve the documentation, and you don’t have to be an expert on pandas to do so! In fact, there are sections of the docs that are worse off after being written by experts. If something in the docs doesn’t make sense to you, updating the relevant section after you figure it out is a great way to ensure it will help the next person.
About the pandas documentation¶
The documentation is written in reStructuredText, which is almost like writing in plain English, and built using Sphinx. The Sphinx Documentation has an excellent introduction to reST. Review the Sphinx docs to perform more complex changes to the documentation as well.
Some other important things to know about the docs:
The pandas documentation consists of two parts: the docstrings in the code itself and the docs in this folder
The docstrings provide a clear explanation of the usage of the individual functions, while the documentation in this folder consists of tutorial-like overviews per topic together with some other information (what’s new, installation, etc).
The docstrings follow a pandas convention, based on the Numpy Docstring Standard. Follow the pandas docstring guide for detailed instructions on how to write a correct docstring.
The tutorials make heavy use of the IPython directive sphinx extension. This directive lets you put code in the documentation which will be run during the doc build. For example:
.. ipython:: python x = 2 x**3
will be rendered as:
In : x = 2 In : x**3 Out: 8
Almost all code examples in the docs are run (and the output saved) during the doc build. This approach means that code examples will always be up to date, but it does make the doc building a bit more complex.
Our API documentation files in
doc/source/referencehouse the auto-generated documentation from the docstrings. For classes, there are a few subtleties around controlling which methods and attributes have pages auto-generated.
We have two autosummary templates for classes.
_templates/autosummary/class.rst. Use this when you want to automatically generate a page for every public method and attribute on the class. The
Methodssections will be automatically added to the class’ rendered documentation by numpydoc. See
DataFramefor an example.
_templates/autosummary/class_without_autosummary. Use this when you want to pick a subset of methods / attributes to auto-generate pages for. When using this template, you should include an
Methodssection in the class docstring. See
CategoricalIndexfor an example.
Every method should be included in a
toctreein one of the documentation files in
doc/source/reference, else Sphinx will emit a warning.
.rst files are used to automatically generate Markdown and HTML versions
of the docs. For this reason, please do not edit
but instead make any changes to
doc/source/development/contributing.rst. Then, to
CONTRIBUTING.md, use pandoc
with the following command:
pandoc doc/source/development/contributing.rst -t markdown_github > CONTRIBUTING.md
The utility script
scripts/validate_docstrings.py can be used to get a csv
summary of the API documentation. And also validate common errors in the docstring
of a specific class, function or method. The summary also compares the list of
methods documented in the files in
doc/source/reference (which is used to generate
the API Reference page)
and the actual public methods.
This will identify methods documented in
doc/source/reference that are not actually
class methods, and existing methods that are not documented in
Updating a pandas docstring¶
When improving a single function or method’s docstring, it is not necessarily
needed to build the full documentation (see next section).
However, there is a script that checks a docstring (for example for the
python scripts/validate_docstrings.py pandas.DataFrame.mean
This script will indicate some formatting errors if present, and will also run and test the examples included in the docstring. Check the pandas docstring guide for a detailed guide on how to format the docstring.
The examples in the docstring (‘doctests’) must be valid Python code, that in a deterministic way returns the presented output, and that can be copied and run by users. This can be checked with the script above, and is also tested on Travis. A failing doctest will be a blocker for merging a PR. Check the examples section in the docstring guide for some tips and tricks to get the doctests passing.
When doing a PR with a docstring update, it is good to post the output of the validation script in a comment on github.
How to build the pandas documentation¶
First, you need to have a development environment to be able to build pandas (see the docs on creating a development environment).
Building the documentation¶
So how do you build the docs? Navigate to your local
doc/ directory in the console and run:
python make.py html
Then you can find the HTML output in the folder
The first time you build the docs, it will take quite a while because it has to run all the code examples and build all the generated docstring pages. In subsequent evocations, sphinx will try to only build the pages that have been modified.
If you want to do a full clean build, do:
python make.py clean python make.py html
You can tell
make.py to compile only a single section of the docs, greatly
reducing the turn-around time for checking your changes.
# omit autosummary and API section python make.py clean python make.py --no-api # compile the docs with only a single section, relative to the "source" folder. # For example, compiling only this guide (doc/source/development/contributing.rst) python make.py clean python make.py --single development/contributing.rst # compile the reference docs for a single function python make.py clean python make.py --single pandas.DataFrame.join # compile whatsnew and API section (to resolve links in the whatsnew) python make.py clean python make.py --whatsnew
For comparison, a full documentation build may take 15 minutes, but a single section may take 15 seconds. Subsequent builds, which only process portions you have changed, will be faster.
The build will automatically use the number of cores available on your machine to speed up the documentation build. You can override this:
python make.py html --num-jobs 4
Open the following file in a web browser to see the full documentation you just built:
And you’ll have the satisfaction of seeing your new and improved documentation!
Building main branch documentation¶
When pull requests are merged into the pandas
main branch, the main parts of
the documentation are also built by Travis-CI. These docs are then hosted here, see also
the Continuous Integration section.
Once, the pull request is submitted, GitHub Actions will automatically build the documentation. To view the built site:
Wait for the
CI / Web and docscheck to complete.
Detailsnext to it.
websiteto download the site as a ZIP file.