internal static BidirectionalGraph <TEdgeData> CreateSubGraph <TEdgeData>(this BidirectionalGraphDirectNodeAccess <TEdgeData> graph,
Dictionary <long, bool> nodesOfSubGraph)
{
var newGraph = new BidirectionalGraph <TEdgeData>();
foreach (var node in nodesOfSubGraph)
{
var newInEdges = newGraph.GetOrCreateInEdges(node.Key);
foreach (var inEdge in graph.InEdges(node.Key))
{
if (nodesOfSubGraph.ContainsKey(inEdge.Source))
{
newInEdges.Add(inEdge);
}
}
var newOutEdges = newGraph.GetOrCreateOutEdges(node.Key);
foreach (var outEdge in graph.OutEdges(node.Key))
{
if (nodesOfSubGraph.ContainsKey(outEdge.Target))
{
newOutEdges.Add(outEdge);
}
}
}
return(newGraph);
}
internal static Dictionary <long, bool> GetAncestors <TEdgeData>(this BidirectionalGraphDirectNodeAccess <TEdgeData> graph,
IEnumerable <long> targetNodes, Func <long, bool> ignoreNodeFunc,
Func <Edge <TEdgeData>, bool> ignoreEdgeFunc = null)
{
// standard behavior: do not ignore node or edge
// node in toNodes are their own ancestors, if they are not ignored by ignoreNodeFunc
// based on DFS https://en.wikipedia.org/wiki/Depth-first_search
var ancestors = new Dictionary <long, bool>();
var nodesToTraverse = new Stack <long>();
foreach (var node in targetNodes)
{
nodesToTraverse.Push(node);
}
while (nodesToTraverse.Count > 0)
{
var currentNode = nodesToTraverse.Pop();
var isIgnored = (ignoreNodeFunc != null && ignoreNodeFunc(currentNode));
var alreadyDiscovered = ancestors.ContainsKey(currentNode);
if (!(isIgnored || alreadyDiscovered))
{
ancestors.Add(currentNode, true);
foreach (var inEdge in graph.InEdges(currentNode))
{
if (ignoreEdgeFunc == null || !ignoreEdgeFunc(inEdge))
{
nodesToTraverse.Push(inEdge.Source);
}
}
}
}
return(ancestors);
}
internal static Dictionary <long, bool> GetAncestors <TEdgeData>(this BidirectionalGraphDirectNodeAccess <TEdgeData> graph,
Dictionary <long, bool> targetNodes)
{
// standard behavior: do not ignore node or edge
// node in toNodes are their own ancestors, if they are not ignored by ignoreNodeFunc
// based on DFS https://en.wikipedia.org/wiki/Depth-first_search
var nodesAdded = new Dictionary <long, bool>();
var nodesToTraverse = new Stack <long>();
foreach (var node in targetNodes)
{
nodesToTraverse.Push(node.Key);
}
while (nodesToTraverse.Count > 0)
{
var currentNode = nodesToTraverse.Pop();
var alreadyDiscovered = nodesAdded.ContainsKey(currentNode);
if (!alreadyDiscovered)
{
nodesAdded.Add(currentNode, true);
foreach (var inEdge in graph.InEdges(currentNode))
{
nodesToTraverse.Push(inEdge.Source);
}
}
}
return(nodesAdded);
}
public BidirectionalGraphSubViewDecorator(BidirectionalGraphDirectNodeAccess <TEdgeData> baseGraph, Func <long, bool> ignoreNodeFunc = null,
Func <Edge <TEdgeData>, bool> ignoreEdgeFunc = null)
{
_baseGraph = baseGraph;
_ignoreNodeFunc = ignoreNodeFunc;
_ignoreEdgeFunc = ignoreEdgeFunc;
}
internal static void GetAncestors(this BidirectionalGraphDirectNodeAccess graph,
Func <int, bool> nodeIsAncestor,
Action <int> nodeSetAncestor,
IEnumerable <int> targetNodes, Func <int, bool> ignoreNodeFunc,
Func <Edge, bool> ignoreEdgeFunc = null)
{
// standard behavior: do not ignore node or edge
// node in toNodes are their own ancestors, if they are not ignored by ignoreNodeFunc
// based on DFS https://en.wikipedia.org/wiki/Depth-first_search
var nodesToTraverse = new Stack <int>();
foreach (var node in targetNodes)
{
nodesToTraverse.Push(node);
}
while (nodesToTraverse.Count > 0)
{
var currentNode = nodesToTraverse.Pop();
var isIgnored = (ignoreNodeFunc != null && ignoreNodeFunc(currentNode));
var alreadyDiscovered = nodeIsAncestor(currentNode);
if (!(isIgnored || alreadyDiscovered))
{
nodeSetAncestor(currentNode);
foreach (var inEdge in graph.InEdges(currentNode))
{
if (ignoreEdgeFunc == null || !ignoreEdgeFunc(inEdge))
{
nodesToTraverse.Push(inEdge.Source);
}
}
}
}
}
public BidirectionalGraphSubViewDecorator(BidirectionalGraphDirectNodeAccess baseGraph, Func <int, bool> ignoreNodeFunc = null, Func <Edge, bool> ignoreEdgeFunc = null)
{
_baseGraph = baseGraph;
_ignoreNodeFunc = ignoreNodeFunc;
_ignoreEdgeFunc = ignoreEdgeFunc;
}
