Reconfillion was released as version 1.0.0 on April 8, 2024. The older version of reconfillion before that date exists on https://github.com/junkawahara/reconfillion-kari , but is not compatible with this version.

Reconfillion is a tool for solving combinatorial reconfiguration problems. It works with graphillion, which means that combinatorial reconfiguration problems of graph classes that are supported by graphillion can be solved by reconfillion.

• Graphillion version v1.7 is needed. Since v1.7 is the latest version and has not been registered into PyPI yet, you need to build it manually.

MIT License

First, clone and install latest Graphillion,

git clone https://github.com/takemaru/graphillion.git

and build it according to the instruction.

Then, clone and install reconfillion:

git clone https://github.com/junkawahara/reconfillion.git
cd reconfillion
pip install .

Let's consider to solve the spanning tree reconfiguration problem. In reconfillion (and graphillion), an edge is represented by a tuple of two vertices, and a graph is represented by a list of edges.

# complete graph with 4 vertices [1, 2, 3, 4]
graph = [(1, 2), (1, 3), (1, 4), (2, 3), (2, 4), (3, 4)]

We import graphillion and reconfillion, and make GraphSet of all the spanning trees on the graph.

from graphillion import GraphSet
from reconfillion import reconf

GraphSet.set_universe(graph) # See the graphillion manual.
spanning_trees = GraphSet.trees(is_spanning = True)

Then, by doing the following method, we can obtain the reconfiguration sequence between s and t.

s = [(1, 2), (1, 3), (1, 4)] # start spanning tree
t = [(1, 4), (2, 4), (3, 4)] # goal spanning tree

# obtain a reconfiguration sequence between s and t under the token jumping model.
reconf_sequence = reconf.get_reconf_seq(s, t, spanning_trees, model = 'tj')

# obtained [[(1, 4), (2, 4), (3, 4)], [(1, 2), (1, 4), (2, 4)], [(1, 2), (1, 3), (1, 4)]]

This software (and graphillion) needs a lot of memory to solve problems with large-size instances.