# Write Document and Tutorials¶

We use the Sphinx for the main documentation. Sphinx support both the reStructuredText and markdown. When possible, we encourage to use reStructuredText as it has richer features. Note that the python doc-string and tutorials allow you to embed reStructuredText syntax.

## Document Python¶

We use numpydoc format to document the function and classes. The following snippet gives an example docstring. We always document all the public functions, when necessary, provide an usage example of the features we support(as shown below).

def myfunction(arg1, arg2, arg3=3):
"""Briefly describe my function.

Parameters
----------
arg1 : Type1
Description of arg1

arg2 : Type2
Description of arg2

arg3 : Type3, optional
Description of arg3

Returns
-------
rv1 : RType1
Description of return type one

Examples
--------
.. code:: python

# Example usage of myfunction
x = myfunction(1, 2)
"""
return rv1


Be careful to leave blank lines between sections of your documents. In the above case, there has to be a blank line before Parameters, Returns and Examples in order for the doc to be built correctly. To add a new function to the doc, we need to add the sphinx.autodoc rules to the docs/api/python). You can refer to the existing files under this folder on how to add the functions.

## Document C++¶

We use the doxgen format to document c++ functions. The following snippet shows an example of c++ docstring.

/*!
* \brief Description of my function
* \param arg1 Description of arg1
* \param arg2 Descroption of arg2
* \returns describe return value
*/
int myfunction(int arg1, int arg2) {
}


## Write Tutorials¶

We use the sphinx-gallery to build python tutorials. You can find the source code under tutorials quite self explanatory. One thing that worth noting is that the comment blocks are written in reStructuredText instead of markdown so be aware of the syntax.

The tutorial code will run on our build server to generate the document page. So we may have a restriction like not being able to access a remote Raspberry Pi, in such case add a flag variable to the tutorial (e.g. use_rasp) and allow users to easily switch to the real device by changing one flag. Then use the existing environment to demonstrate the usage.

## Refer to Another Location in the Document¶

Please use sphinx’s :ref: markup to refer to another location in the same doc.

.. _document-my-section-tag

My Section
----------

You can use :ref:document-my-section-tag to refer to My Section.