Example #1
0
        /// <summary>
        /// Adds edgeCount number of edges to network.  AllowMultiEdges and AllowSelfLoops will affect
        /// how edges are added.
        /// </summary>
        public static void CreateEdges(INetworkAdjList network, int edgeCount)
        {
            Random rand = new Random(DateTime.Now.Millisecond);

            int srcNodeIndex = -1;
            int destNodeIndex = -1;
            INode srcNode = null;
            INode destNode = null;

            for (int i = 0; i < edgeCount; i++)
            {
                srcNodeIndex = rand.Next(network.NodeCount);
                destNodeIndex = rand.Next(network.NodeCount);
                srcNode = network.Nodes[srcNodeIndex];
                destNode = network.Nodes[destNodeIndex];

                if (!AllowMultiEdges && AllowSelfLoops)
                {
                    if (network.IsEdge(srcNode, destNode))
                        continue;
                    else
                        network.CreateEdge(srcNode, destNode);
                }
                else if (AllowMultiEdges && !AllowSelfLoops)
                {
                    if (srcNode == destNode)
                        continue;
                    else
                        network.CreateEdge(srcNode, destNode);
                }
                else
                    network.CreateEdge(srcNode, destNode);
            }
        }
        public void GarunteeEdgeCount(int edgeCount, INetworkAdjList network)
        {
            Random rand = new Random();
            while (network.EdgeCount < edgeCount)
            {
                int index0 = rand.Next(network.EdgeCount);
                int index1 = rand.Next(network.EdgeCount);

                INode node0 = network.Nodes[index0];
                INode node1 = network.Nodes[index1];

                network.CreateEdge(node0, node1);
            }
        }
Example #3
0
        /// <summary>
        ///  Ensures a minimum number of self loops exist in the network.
        /// </summary>
        public static void EnsureMinSelfLoopCount(INetworkAdjList network, int n)
        {
            int ctr = 0;
            foreach (IEdge edge in network.EdgeEnumerator)
            {
                if (edge.IsSelfLoop)
                    ctr++;
            }

            // if that many self loops exist, return
            if (ctr>=n)
                return;

            // else create the needed number of self loops
            int needed = n;
            if (n<ctr)
                needed = ctr-n;

            ctr=0;  // re-use ctr variable
            do
            {
                foreach (INode node in network.NodeEnumerator)
                {
                    network.CreateEdge(node, node);
                    ctr++;
                    if (ctr>=needed)
                        break;
                }
            } while (needed>ctr);
        }