private SimpleGraph<Integer, DefaultEdge> buildGraphForTestDisconnected(int size) {
SimpleGraph<Integer, DefaultEdge> graph = new SimpleGraph<>(DefaultEdge.class);
VertexFactory<Integer> vertexFactory = new IntegerVertexFactory();
CompleteGraphGenerator<Integer, DefaultEdge> completeGraphGenerator =
new CompleteGraphGenerator<>(size);
// two complete graphs
SimpleGraph<Integer, DefaultEdge> east = new SimpleGraph<>(DefaultEdge.class);
completeGraphGenerator.generateGraph(east, vertexFactory, null);
SimpleGraph<Integer, DefaultEdge> west = new SimpleGraph<>(DefaultEdge.class);
completeGraphGenerator.generateGraph(west, vertexFactory, null);
Graphs.addGraph(graph, east);
Graphs.addGraph(graph, west);
// connected by single edge
graph.addEdge(size - 1, size);
return graph;
}
protected Graph<String, DefaultWeightedEdge> createWithBias(boolean negate) {
Graph<String, DefaultWeightedEdge> g;
double bias = 1;
if (negate) {
// negative-weight edges are being tested, so only a directed graph
// makes sense
g = new SimpleDirectedWeightedGraph<String, DefaultWeightedEdge>(DefaultWeightedEdge.class);
bias = -1;
} else {
// by default, use an undirected graph
g = new SimpleWeightedGraph<String, DefaultWeightedEdge>(DefaultWeightedEdge.class);
}
g.addVertex(V1);
g.addVertex(V2);
g.addVertex(V3);
g.addVertex(V4);
g.addVertex(V5);
e12 = Graphs.addEdge(g, V1, V2, bias * 2);
e13 = Graphs.addEdge(g, V1, V3, bias * 3);
e24 = Graphs.addEdge(g, V2, V4, bias * 5);
e34 = Graphs.addEdge(g, V3, V4, bias * 20);
e45 = Graphs.addEdge(g, V4, V5, bias * 5);
e15 = Graphs.addEdge(g, V1, V5, bias * 100);
return g;
}