roughness operator

[fmagrini]

Espresso Pull Request Template

Description

Please provide a clear and concise description of the changes you've made.

If you are adding a new EspressoProblem, read the Contributor's Guide as a reference. Otherwise refer to the Developer's Guide.

Type of Change

Please indicate the type of change this pull request represents:

• [ ] New Espresso problem or example
• [ ] Espresso core
• [ ] Espresso machine
• [ ] Documentation
• [x] Others (please specify here)

Checklist for new EspressoProblem (remove me if not applicable)

Requirements

Please list any requirements or dependencies for running the problem here.

Additional information

Provide any additional information on how to run the problem or context about it here.

Jupyter Notebook

If applicable, provide a brief description of the Jupyter notebook included with this problem.

Testing

To validate your problem:

$ python espresso_machine/build_package/build.py --pre --post -c <example_name>

Please confirm that you have tested your problem:

• [x] I have checked that all tests pass locally with my changes
• [x] I have ensured that my code follows the style guidelines of this project

Licence

Confirm the licence under which this problem is distributed.

Checklist for Espresso core (remove me if not applicable)

• [ ] My changes are backward compatible
• [ ] The new contribution generation script is compatible with the new changes
• [ ] The build script is compatible with the new changes
• [ ] The validation script is compatible with the new changes
• [ ] The documentation is up to date with the new changes
• [ ] I have formatted the Python files with black

Checklist for Espresso machine (remove me if not applicable)

• [ ] My changes are backward compatible
• [ ] The documentation is up to date with the new changes
• [ ] I have formatted the Python files with black

Checklist for Espresso documentation (remove me if not applicable)

• [ ] I have built the documentation by running make html in the docs/ folder
• [ ] I have served the website locally by running python -m http.server 8000 -d build/html and checked the changes at localhost:8000

Additional Information

Please provide any additional information or context about the pull request here.