How to document CEA?

Documentation language

The documentation language of the City Energy Analyst is American English.

The documentation is written using a markup language called reStructuredText (rst) and is rendered by Sphinx. The Quick reStructuredText is a great introductory resource for writing rst documentation for CEA.

Module Documentation

The most common tool for documenting methods and functions within Python code is the Field List. Only documentation strings within the """ Three Quotation Marks """ will be parsed by Sphinx when rendering the API documentation, with # Python comments ignored.

Module Documentation Standard Example:

Title of module without section denotation

def method(parameter1, parameter2):
    This method does this and that

    The following file is created:
        - output_file: .pdf Plot of some variables.

    :param parameter1: a list of variables
    :type list: List[]
    :param parameter2: the filename (pdf) to save the results as.
    :type output_file: str

    :return: if anything is returned


 # these comments are ignored by Sphinx

You can check if your documentation will render as intended using the Online Sphinx Editor. Bear in mind, some documentation strings will still malfunction but it’s a great starting point.

Sphinx Tools

Once you are ready to generate the API for your new or altered module, a couple of tools exist to assist you. You can run these from anaconda prompt within the docs repository: CityEnergyAnalyst\docs. Please ensure you have activated the cea virtual environment by calling activate cea.

You can run the batch files by typing the following titles:


This batch file runs sphinx-build , stopping the build when the first error is encountered. This tool is great for de-bugging documentation builds, allowing you to check and fix errors one by one.


This batch file will delete all the existing auto-generated module documentation, i.e. cea*.rst files, within the CityEnergyAnalyst\docs\modules repository. Then, it will run the sphinx-apidoc function, rebuilding the documentation for all modules in the CityEnergyAnalyst\cea repository.

Note, the following paths/modules are currently excluded due to module import errors:


TO DO: Check/update cea VE to include missing modules.

make clean

This extension of the make.bat removes the contents of the CityEnergyAnalyst\docs\build repository, containing all the html files and TOC trees generated from previous sphinx-build. This tool should be run in conjunction with make-api-doc when major changes to documentation occur, such as the addition of new modules.

make html

This extension of the make batch runs sphinx-build to generate html files in the CityEnergyAnalyst\docs\_build from each of the rst files within the CityEnergyAnalyst\docs and CityEnergyAnalyst\docs\modules repositories. This tool will generate html files from any new rst files created since the last build, skipping pre-existing rst and corresponding html files.