Compute a maximum-weighted matching in the undirected, weighted graph G.
If maxcardinality is True, compute the maximum-cardinality matching with maximum weight among all maximum-cardinality matchings.
The matching is returned as a dictionary, mate, such that mate[v] == w if node v is matched to node w. Unmatched nodes do not occur as a key in mate.
A matching is a subset of edges in which no node occurs more than once. The cardinality of a matching is the number of matched edges. The weight of a matching is the sum of the weights of its edges.
If G is an XGraph, the edge data are used as weight values; if G is a Graph, all edge weights are taken to be 1. Directed graphs and multi-edge graphs are not supported.
This function takes time O(number_of_nodes ** 3).
If all edge weights are integers, the algorithm uses only integer computations. If floating point weights are used, the algorithm could return a slightly suboptimal matching due to numeric precision errors.