⚠ Warning

This code is in a pre-release state. It may not be fully functional and breaking changes can occur without notice.

Gurobi Model Analyzer is an open-source python package that provides detailed analysis of model solutions and model characteristics. Version 1.0 consists of a results_analyzer module that calculates explanations of ill-conditioned basis matrices.

Note: At the moment this repository is public, but final docs configuration and packages is not yet finished. We recommend that you hold off on using it until version 1.0 is announced as available.

The latest user manual is available on readthedocs.

For questions related to using Gurobi Model Analyzer, please use Gurobi's Forum.

For reporting bugs, issues, and feature requests please open an issue.

If you encounter issues with Gurobi or gurobipy please contact Gurobi Support.

• Python >= 3.9
• numpy >= 1.21.5 (although earlier versions compatible with python 3.7 will probably work).

The easiest way to install gurobi-modelanalyzer is using pip in a virtual environment:

(.venv) pip install gurobi-modelanalyzer

This will also install the numpy and gurobipy dependencies.

Please note that gurobipy is commercial software and requires a license. When installed via pip or conda, gurobipy ships with a free license for testing and can only solve models of limited size.

Then use the explainer functions. Example usage

import gurobipy as gp
import model_analyzer.results_analyzer as ra
model=gp.read("myillconditionedmodel.mps")
model.optimize()
ra.kappa_explain(model)

# row-based explanation (default)
ra.kappa_explain(model, expltype="ROWS")

# column-based explanation
ra.kappa_explain(model, expltype="COLS")

# angle-based explanation (only looks for pairs of rows or columns
# that cause ill-conditioning.
ra.angle_explain(model)

Use help(ra.kappa_explain) or help(ra.angle_explain) for information on more advanced usage.

Alternatively to the bundled limited license, there are licenses that can handle models of all sizes.

As a student or staff member of an academic institution you qualify for a free, full product license. For more information, see:

• https://www.gurobi.com/academia/academic-program-and-licenses/

For a commercial evaluation, you can request an evaluation license.

Other useful resources to get started:

• https://www.gurobi.com/documentation/
• https://support.gurobi.com/hc/en-us/community/topics/

We value any level of experience in using Gurobi Model Analyzer and would like to encourage you to contribute directly to this project. Please see the Contributing Guide for more information.

You can clone the latest sources with the command:

git clone [email protected]:Gurobi/gurobi-modelanalyzer.git

Before opening a Pull Request, have a look at the full Contributing page to make sure your code complies with our guidelines.