cutgeneratingfunctionology 1.4

Python code for computation and experimentation with cut-generating functions

Most of the code is for the 1-dimensional Gomory-Johnson infinite group problem, including an electronic compendium of extreme functions.

See the survey “Light on the Infinite Group Relaxation” (http://www.optimization-online.org/DB_HTML/2014/10/4620.html) for the mathematical background and a table of functions in the electronic compendium. See also the paper “An electronic compendium of extreme functions for the Gomory–Johnson infinite group problem” (http://www.optimization-online.org/DB_HTML/2014/11/4646.html) for a discussion of several functions in the compendium.

See http://www.sagemath.org/doc/tutorial/ for information on how to use Sage.

Authors

See file AUTHORS.rst and also THANKS.rst

License

The code is released under the GNU General Public License, version 2, or any later version as published by the Free Software Foundation.

Documentation

http://mkoeppe.github.io/cutgeneratingfunctionology/doc/html/

Run it on mybinder.org

How to run the code in a local copy of Sage

1. Download the code from https://github.com/mkoeppe/cutgeneratingfunctionology.git

2. Install SageMath:

   1. Either from source from http://www.sagemath.org/

   2. or with a binary from http://www.sagemath.org/

   3. or via conda (recommended):

      • Install Miniconda from https://docs.conda.io/en/latest/miniconda.html

      • From the directory “cutgeneratingfunctionology”, set up the environment:

        conda env create -n sage-cgf -f environment.yml
        conda activate sage-cgf

3. From the directory “cutgeneratingfunctionology”, start Sage. You can either use the terminal (IPython):

   sage

   or a Jupyter notebook:

   sage -n jupyter

4. At the Sage prompt, type:

   import cutgeneratingfunctionology.igp as igp; from cutgeneratingfunctionology.igp import *

5. Follow the instructions and examples in demo.rst.

How to run the code online via cloud.sagemath.com

1. Create a user account at https://cloud.sagemath.com

2. Log in at https://cloud.sagemath.com

3. Create a new project “Group relaxation” (or any name)

4. Open the project

5. Create a directory: Paste in the weblink: https://github.com/mkoeppe/cutgeneratingfunctionology.git and hit enter

6. Enter that directory

7. Click “+ New”, select “Sage worksheet”

8. Type:

   import cutgeneratingfunctionology.igp as igp; from cutgeneratingfunctionology.igp import *

   and hit shift+enter

9. Follow the instructions and examples in demo.sage.

To update the code to the latest version:

1. In the project “Group relaxation”, open the directory “cutgeneratingfunctionology”.

2. In the line “Terminal command…”, enter:

   git pull