private double calcualteDeltaModularity(V i, Set<V> groupC, Graph<V, E> graph) {
		double dQshort = 0;
		double sumTot = 0;
		double ki = 0;
		double kiIn = 0;

		for (V v1 : groupC) {

			for (V v3 : graph.getNeighbors(v1)) {
				E e = graph.findEdge(v1, v3);
				if (groupC.contains(v3)) {
					sumTot += 0.5 * edgesValues.get(e);
				} else {
					sumTot += edgesValues.get(e);
				}
			}
			E e = graph.findEdge(i, v1);
			if (e != null) {
				kiIn += edgesValues.get(e);
			}
		}

		for (E e : graph.getIncidentEdges(i)) {
			ki += edgesValues.get(e);
		}
		dQshort = (kiIn / m2) - (2 * sumTot * ki / (m2 * m2));
		return dQshort;
	}