Source code for qrisp.qiro.qiroproblems.qiroMaxSetPack

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"""Transforms a Maximum Set Packing instance into an equivalent Maximum Independent Set graph."""

from itertools import combinations

import networkx as nx



[docs]
def transform_max_set_pack_to_mis(problem):
    """Transforms a Maximum Set Packing problem instance into a Maximum Independent Set (MIS) problem instance.

    Parameters
    ----------
     problem : list[set]
         A list of sets specifying the problem.

    Returns
    -------
     G : nx.Graph
         The corresponding graph to be solved by an MIS implementation.


    """

    def non_empty_intersection(problem):
        return [(i, j) for (i, s1), (j, s2) in combinations(enumerate(problem), 2) if s1.intersection(s2)]

    # create constraint graph
    G = nx.Graph()
    G.add_nodes_from(range(len(problem)))
    G.add_edges_from(non_empty_intersection(problem))

    return G