Feature proposal: Add restricted/allowed assignments to quadratic_assignment()

Contributor & Development Discussion scipy
1

Hello SciPy developers and maintainers,

During my PhD, I modified the implementation of the ‘faq' algorithm inside scipy.optimize.quadratic_assignment() so that it can handle forbidden assignments between nodes.

Motivation

During my PhD in neuroscience, I frequently needed to forbid certain node-to-node mappings, and I believe that restricting the assignment of a node to only a subset of nodes would be useful for other scientific domains.

Proposed feature

Add a new optional argument, for example allowed, which is a boolean matrix of shape (n_nodes, n_nodes).

  • allowed[i, j] = True means assignment of node i to node j is allowed,

  • allowed[i, j] = False means this assignment is forbidden.

The FAQ algorithm would then respect these constraints when solving the quadratic assignment problem.

I would be happy to open a pull request for this implementation, including documentation and tests. So please let me know if this feature is worth integrating.

Thank you for your time and for maintaining SciPy!

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How substantial is the modification, a few lines or many?

3

A few lines,

Thank you,

Yanis