pysumma is a Python wrapper for manipulating, running, managing, and analyzing of SUMMA (Structure for Unifying Multiple Modeling Alternatives)

pysumma provides methods for:
  • Running SUMMA

  • Modifying SUMMA input files

  • Automatically parallelizing distributed and sensitivity analysis type experiments

  • Visualizing output


pysumma can be installed from either conda or pip. Installation using conda is preferred, because it will also install a compatible version of SUMMA.

To install via conda use:

conda install -c conda-forge pysumma

To install via pip use:

pip install pysumma


A conda environment is available for management of pysumma’s dependencies. You can create your own environment from this file by running:

conda env create -f environment.yml

Then, you can activate this environment with conda activate pysumma. Before installing pysumma into this environment you may also wish to install it as a kernel in your Jupyter environments. This can be accomplished by running:

python -m ipykernel install --user --name=pysumma

With this environment active you can install pysumma this environment with the instructions below.

Installing pysumma from source

Installing pysumma from source can be useful for developing new features. This can be accomplished by running:

git clone
cd pysumma
python develop

Additional SUMMA References


Our issue tracker is at Please report any bugs that you find. Or, even better, fork the repository on GitHub and create a pull request. All changes are welcome, big or small, and we will help you make the pull request if you are new to git (just ask on the issue).