/// <summary>
/// Returns true if there is at least one connectivity cycle within the provided INetworkDefinition.
/// </summary>
public bool IsNetworkCyclicInternal(INetworkDefinition networkDef)
{
// Clear any existing state (allow reuse of this class).
_ancestorNodeSet.Clear();
_visitedNodeSet.Clear();
// Get and store connectivity data for the network.
_networkConnectivityData = networkDef.GetConnectivityData();
// Loop over all nodes. Take each one in turn as a traversal root node.
foreach (INetworkNode node in networkDef.NodeList)
{
// Determine if the node has already been visited.
if (_visitedNodeSet.Contains(node.Id))
{ // Already traversed; Skip.
continue;
}
// Traverse into the node.
if (TraverseNode(node.Id))
{ // Cycle detected.
return(true);
}
}
// No cycles detected.
return(false);
}
/// <summary>
/// Calculate node depths in an acyclic network.
/// </summary>
public NetworkDepthInfo CalculateNodeDepths(INetworkDefinition networkDef)
{
// Clear any existing state (allow reuse of this class).
_nodeDepthById.Clear();
// Get and store connectivity data for the network.
_networkConnectivityData = networkDef.GetConnectivityData();
// Loop over all input (and bias) nodes; Perform a depth first traversal of each in turn.
// Set of nodes visited in the current traversal (reset before each individual depth first traversal).
HashSet <uint> visitedNodeSet = new HashSet <uint>();
int inputAndBiasCount = networkDef.InputNodeCount + 1;
for (int i = 0; i < inputAndBiasCount; i++)
{
visitedNodeSet.Clear();
TraverseNode(_networkConnectivityData.GetNodeDataByIndex(i), visitedNodeSet, 0);
}
// Extract node depths from _nodeDepthById into an array of depths (node depth by node index).
// Note. Any node not in the dictionary is in an isolated sub-network and will be assigned to
// layer 0 by default.
INodeList nodeList = networkDef.NodeList;
int nodeCount = nodeList.Count;
int[] nodeDepthArr = new int[nodeCount];
int maxDepth = 0;
// Loop over nodes and set the node depth. Skip over input and bias nodes, they are defined as
// being in layer zero.
for (int i = inputAndBiasCount; i < nodeCount; i++)
{
// Lookup the node's depth. If not found depth remains set to zero.
int depth;
if (_nodeDepthById.TryGetValue(nodeList[i].Id, out depth))
{
nodeDepthArr[i] = depth;
// Also determine maximum depth, that is, total depth of the network.
if (depth > maxDepth)
{
maxDepth = depth;
}
}
}
// Return depth analysis info.
return(new NetworkDepthInfo(maxDepth + 1, nodeDepthArr));
}
/// <summary>
/// Calculate node depths in an acyclic network.
/// </summary>
public NetworkDepthInfo CalculateNodeDepths(INetworkDefinition networkDef)
{
// Clear any existing state (allow reuse of this class).
_nodeDepthById.Clear();
// Get and store connectivity data for the network.
_networkConnectivityData = networkDef.GetConnectivityData();
// Loop over all input (and bias) nodes; Perform a depth first traversal of each in turn.
// Set of nodes visited in the current traversal (reset before each individual depth first traversal).
HashSet<uint> visitedNodeSet = new HashSet<uint>();
int inputAndBiasCount = networkDef.InputNodeCount + 1;
for(int i=0; i<inputAndBiasCount; i++)
{
visitedNodeSet.Clear();
TraverseNode(_networkConnectivityData.GetNodeDataByIndex(i), visitedNodeSet, 0);
}
// Extract node depths from _nodeDepthById into an array of depths (node depth by node index).
// Note. Any node not in the dictionary is in an isolated sub-network and will be assigned to
// layer 0 by default.
INodeList nodeList = networkDef.NodeList;
int nodeCount = nodeList.Count;
int[] nodeDepthArr = new int[nodeCount];
int maxDepth = 0;
// Loop over nodes and set the node depth. Skip over input and bias nodes, they are defined as
// being in layer zero.
for(int i=inputAndBiasCount; i<nodeCount; i++)
{
// Lookup the node's depth. If not found depth remains set to zero.
int depth;
if(_nodeDepthById.TryGetValue(nodeList[i].Id, out depth))
{
nodeDepthArr[i] = depth;
// Also determine maximum depth, that is, total depth of the network.
if(depth > maxDepth) {
maxDepth = depth;
}
}
}
// Return depth analysis info.
return new NetworkDepthInfo(maxDepth+1, nodeDepthArr);
}
/// <summary>
/// Gets NetworkConnectivityData for the network.
/// </summary>
public NetworkConnectivityData GetConnectivityData()
{
if (null != _networkConnectivityData)
{
return(_networkConnectivityData);
}
int nodeCount = _nodeList.Count;
NodeConnectivityData[] nodeConnectivityDataArr = new NodeConnectivityData[nodeCount];
Dictionary <uint, NodeConnectivityData> nodeConnectivityDataById = new Dictionary <uint, NodeConnectivityData>(nodeCount);
// Instantiate NodeConnectivityData for each node.
for (int i = 0; i < nodeCount; i++)
{
uint nodeId = _nodeList[i].Id;
NodeConnectivityData ncd = new NodeConnectivityData(nodeId);
nodeConnectivityDataArr[i] = ncd;
nodeConnectivityDataById.Add(nodeId, ncd);
}
// Loop connections and register them with the source and target nodes.
int conCount = _connectionList.Count;
for (int i = 0; i < conCount; i++)
{
INetworkConnection conn = _connectionList[i];
NodeConnectivityData srcNodeData = nodeConnectivityDataById[conn.SourceNodeId];
NodeConnectivityData tgtNodeData = nodeConnectivityDataById[conn.TargetNodeId];
srcNodeData._tgtNodes.Add(conn.TargetNodeId);
tgtNodeData._srcNodes.Add(conn.SourceNodeId);
}
_networkConnectivityData = new NetworkConnectivityData(nodeConnectivityDataArr, nodeConnectivityDataById);
return(_networkConnectivityData);
}
/// <summary>
/// Gets NetworkConnectivityData for the network.
/// </summary>
public NetworkConnectivityData GetConnectivityData()
{
if(null != _networkConnectivityData) {
return _networkConnectivityData;
}
int nodeCount = _nodeList.Count;
NodeConnectivityData[] nodeConnectivityDataArr = new NodeConnectivityData[nodeCount];
Dictionary<uint,NodeConnectivityData> nodeConnectivityDataById = new Dictionary<uint,NodeConnectivityData>(nodeCount);
// Instantiate NodeConnectivityData for each node.
for(int i=0; i<nodeCount; i++)
{
uint nodeId = _nodeList[i].Id;
NodeConnectivityData ncd = new NodeConnectivityData(nodeId);
nodeConnectivityDataArr[i] = ncd;
nodeConnectivityDataById.Add(nodeId, ncd);
}
// Loop connections and register them with the source and target nodes.
int conCount = _connectionList.Count;
for(int i=0; i<conCount; i++)
{
INetworkConnection conn = _connectionList[i];
NodeConnectivityData srcNodeData = nodeConnectivityDataById[conn.SourceNodeId];
NodeConnectivityData tgtNodeData = nodeConnectivityDataById[conn.TargetNodeId];
srcNodeData._tgtNodes.Add(conn.TargetNodeId);
tgtNodeData._srcNodes.Add(conn.SourceNodeId);
}
_networkConnectivityData = new NetworkConnectivityData(nodeConnectivityDataArr, nodeConnectivityDataById);
return _networkConnectivityData;
}
/// <summary>
/// Returns true if there is at least one connectivity cycle within the provided INetworkDefinition.
/// </summary>
public bool IsNetworkCyclicInternal(INetworkDefinition networkDef)
{
// Clear any existing state (allow reuse of this class).
_ancestorNodeSet.Clear();
_visitedNodeSet.Clear();
// Get and store connectivity data for the network.
_networkConnectivityData = networkDef.GetConnectivityData();
// Loop over all nodes. Take each one in turn as a traversal root node.
foreach(INetworkNode node in networkDef.NodeList)
{
// Determine if the node has already been visited.
if(_visitedNodeSet.Contains(node.Id))
{ // Already traversed; Skip.
continue;
}
// Traverse into the node.
if(TraverseNode(node.Id))
{ // Cycle detected.
return true;
}
}
// No cycles detected.
return false;
}
