public static IDictionary <int, double> Get(UndirectedGraph <int, Edge <int> > g)
{
var dfs = new UndirectedDepthFirstSearchAlgorithm <int, Edge <int> >(g);
var recorder = new UndirectedVertexDistanceRecorderObserver <int, Edge <int> >(edgeWeights => 1.0);
using (recorder.Attach(dfs))
{
dfs.Compute();
return(recorder.Distances);
}
}
public static IDictionary <string, double> Get(UndirectedGraph <string, TaggedEdge <string, string> > g)
{
var dfs = new UndirectedDepthFirstSearchAlgorithm <string, TaggedEdge <string, string> >(g);
var recorder = new UndirectedVertexDistanceRecorderObserver <string, TaggedEdge <string, string> >(edgeWeights => double.Parse(edgeWeights.Tag));
using (recorder.Attach(dfs))
{
dfs.Compute();
return(recorder.Distances);
}
}
public void Constructor()
{
Func <Edge <int>, double> edgeWeights = edge => 1.0;
var recorder = new UndirectedVertexDistanceRecorderObserver <int, Edge <int> >(edgeWeights);
Assert.AreSame(edgeWeights, recorder.EdgeWeights);
Assert.IsNotNull(recorder.DistanceRelaxer);
Assert.IsNotNull(recorder.Distances);
var distances = new Dictionary <int, double>();
recorder = new UndirectedVertexDistanceRecorderObserver <int, Edge <int> >(
edgeWeights,
DistanceRelaxers.ShortestDistance,
distances);
Assert.AreSame(edgeWeights, recorder.EdgeWeights);
Assert.AreSame(DistanceRelaxers.ShortestDistance, recorder.DistanceRelaxer);
Assert.AreSame(distances, recorder.Distances);
}
/// <summary>
/// Compute
/// </summary>
private void Form_Load(object sender, EventArgs e)
{
// Crete distance table
tableDijkstra.Columns.Add();
tableDijkstra.Rows.Add(tableDijkstra.NewRow());
for (var i = 0; i < FormMain.nodes.Count; i++)
{
tableDijkstra.Columns.Add();
tableDijkstra.Rows.Add(tableDijkstra.NewRow());
tableDijkstra.Rows[0][i + 1] = tableDijkstra.Rows[i + 1][0] = i;
}
// Create graph
var graph = new UndirectedGraph <int, Edge <int> >();
// Add vertices to the graph
for (var i = 0; i < FormMain.nodes.Count; i++)
{
graph.AddVertex(i);
}
// Create edges
for (var i = 0; i < FormMain.edges.Count; i++)
{
var quickGraphEdge = new Edge <int>(FormMain.nodes.IndexOf(FormMain.edges[i].nodes[0]), FormMain.nodes.IndexOf(FormMain.edges[i].nodes[1]));
graph.AddEdge(quickGraphEdge);
}
// Compute distances
for (var source = 0; source < FormMain.nodes.Count; source++)
{
// We want to use Dijkstra on this graph
var dijkstra = new UndirectedDijkstraShortestPathAlgorithm <int, Edge <int> >(graph, edge => 1);
// attach a distance observer to give us the shortest path distances
var distObserver = new UndirectedVertexDistanceRecorderObserver <int, Edge <int> >(edge => 1);
distObserver.Attach(dijkstra);
// Attach a Vertex Predecessor Recorder Observer to give us the paths
var predecessorObserver = new UndirectedVertexPredecessorRecorderObserver <int, Edge <int> >();
predecessorObserver.Attach(dijkstra);
// Run the algorithm for current Node
dijkstra.Compute(source);
// Show distances
foreach (var target in distObserver.Distances)
{
tableDijkstra.Rows[source + 1][target.Key + 1] = target.Value.ToString();
IEnumerable <Edge <int> > edgePath;
if (predecessorObserver.TryGetPath(target.Key, out edgePath))
{
string str = " (";
foreach (var nodeID in edgePath.Select(edge => edge.Source).Concat(edgePath.Select(edge => edge.Target)).Distinct().OrderBy(next => distObserver.Distances[next]))
{
str += string.Format("{0}->", nodeID);
}
tableDijkstra.Rows[source + 1][target.Key + 1] += str.Substring(0, str.Length - 2) + ")";
}
}
}
dataGridView.AutoSizeColumnsMode = DataGridViewAutoSizeColumnsMode.AllCellsExceptHeader;
}
public static string ShortestWayDijsktraAlgorithmUnDirected(GraphVertex vertexD, List <GraphEdge> listEdge, List <GraphVertex> listVertex)
{
string s = "";
UndirectedGraph <GraphVertex, UndirectedEdge <GraphVertex> > graph = new UndirectedGraph <GraphVertex, UndirectedEdge <GraphVertex> >();
foreach (var vert in listVertex)
{
graph.AddVertex(vert);
}
foreach (var edge in listEdge)
{
graph.AddEdge(new UndirectedEdge <GraphVertex>(edge.StartVertex, edge.EndVertex));
}
Dictionary <UndirectedEdge <GraphVertex>, double> edgeCost = new Dictionary <UndirectedEdge <GraphVertex>, double>();
int i = 0;
foreach (var edge in graph.Edges)
{
double eCost = EdgeCostSearching(edge.Source, edge.Target, listEdge);
edgeCost.Add(edge, eCost);
i++;
}
IEnumerable <UndirectedEdge <GraphVertex> > pathh;
Func <UndirectedEdge <GraphVertex>, double> getW = edge => edgeCost[edge];
UndirectedDijkstraShortestPathAlgorithm <GraphVertex, UndirectedEdge <GraphVertex> > diijkstra = new UndirectedDijkstraShortestPathAlgorithm <GraphVertex, UndirectedEdge <GraphVertex> >(graph, getW);
UndirectedVertexDistanceRecorderObserver <GraphVertex, UndirectedEdge <GraphVertex> > distObs = new UndirectedVertexDistanceRecorderObserver <GraphVertex, UndirectedEdge <GraphVertex> >(getW);
using (distObs.Attach(diijkstra))
{
UndirectedVertexPredecessorRecorderObserver <GraphVertex, UndirectedEdge <GraphVertex> > predObs = new UndirectedVertexPredecessorRecorderObserver <GraphVertex, UndirectedEdge <GraphVertex> >();
using (predObs.Attach(diijkstra))
{
diijkstra.Compute(vertexD);
foreach (KeyValuePair <GraphVertex, double> kvp in distObs.Distances)
{
s += "From " + vertexD.Name + " to " + kvp.Key.Name + " is " + kvp.Value + " by ";
if (predObs.TryGetPath(kvp.Key, out pathh))
{
foreach (var t in pathh)
{
s += "edge " + t.Source.Name + "<->" + t.Target.Name + " ";
}
}
s += System.Environment.NewLine;
}
}
}
return(s);
}
public void Attach()
{
// Undirected DFS is used for tests but result may change if using another search algorithm
// or another starting point
{
var recorder = new UndirectedVertexDistanceRecorderObserver <int, Edge <int> >(edge => 1.0);
var graph = new UndirectedGraph <int, Edge <int> >();
var dfs = new UndirectedDepthFirstSearchAlgorithm <int, Edge <int> >(graph);
using (recorder.Attach(dfs))
{
dfs.Compute();
CollectionAssert.IsEmpty(recorder.Distances);
}
}
{
var recorder = new UndirectedVertexDistanceRecorderObserver <int, Edge <int> >(edge => 1.0);
var graph = new UndirectedGraph <int, Edge <int> >();
graph.AddVertexRange(new[] { 1, 2 });
var dfs = new UndirectedDepthFirstSearchAlgorithm <int, Edge <int> >(graph);
using (recorder.Attach(dfs))
{
dfs.Compute();
CollectionAssert.IsEmpty(recorder.Distances);
}
}
{
var recorder = new UndirectedVertexDistanceRecorderObserver <int, Edge <int> >(edge => 1.0);
var edge12 = new Edge <int>(1, 2);
var edge14 = new Edge <int>(1, 4);
var edge31 = new Edge <int>(3, 1);
var edge33 = new Edge <int>(3, 3);
var edge34 = new Edge <int>(3, 4);
var edge42 = new Edge <int>(4, 2);
var graph = new UndirectedGraph <int, Edge <int> >();
graph.AddVerticesAndEdgeRange(new[]
{
edge12, edge14, edge31, edge33, edge34, edge42
});
var dfs = new UndirectedDepthFirstSearchAlgorithm <int, Edge <int> >(graph);
using (recorder.Attach(dfs))
{
dfs.Compute();
CollectionAssert.AreEqual(
new Dictionary <int, double>
{
[1] = 0,
[2] = 1,
[3] = 3,
[4] = 2
},
recorder.Distances);
}
}
}
public static void createTables()
{
// Create graph
var graph = new UndirectedGraph<int, Edge<int>>();
// Add vertices to the graph
for (var i = 0; i < FormMain.nodes.Count; i++)
graph.AddVertex(i);
// Create edges
var edgeCost = new Dictionary<Edge<int>, double>();
for (var i = 0; i < FormMain.edges.Count; i++)
{
var quickGraphEdge = new Edge<int>(FormMain.nodes.IndexOf(FormMain.edges[i].nodes[0]), FormMain.nodes.IndexOf(FormMain.edges[i].nodes[1]));
graph.AddEdge(quickGraphEdge);
edgeCost.Add(quickGraphEdge, FormMain.edges[i].Weight);
}
// Initialize tables
distanceTable = new double[FormMain.nodes.Count, FormMain.nodes.Count];
pathTable = new List<int>[FormMain.nodes.Count, FormMain.nodes.Count];
for (var i = 0; i < FormMain.nodes.Count; i++)
for (var j = 0; j < FormMain.nodes.Count; j++)
{
distanceTable[i, j] = double.PositiveInfinity;
pathTable[i, j] = new List<int>();
}
// Create tables
for (var source = 0; source < FormMain.nodes.Count; source++)
{
// We want to use Dijkstra on this graph
var dijkstra = new UndirectedDijkstraShortestPathAlgorithm<int, Edge<int>>(graph, edge => edgeCost[edge]);
// attach a distance observer to give us the shortest path distances
var distObserver = new UndirectedVertexDistanceRecorderObserver<int, Edge<int>>(edge => edgeCost[edge]);
distObserver.Attach(dijkstra);
// Attach a Vertex Predecessor Recorder Observer to give us the paths
var predecessorObserver = new UndirectedVertexPredecessorRecorderObserver<int, Edge<int>>();
predecessorObserver.Attach(dijkstra);
// Run the algorithm for current Node
dijkstra.Compute(source);
// Add values to table
foreach (var target in distObserver.Distances)
{
distanceTable[source, target.Key] = target.Value;
IEnumerable<Edge<int>> path;
if (predecessorObserver.TryGetPath(target.Key, out path))
pathTable[source, target.Key].AddRange(path.Select(edge => edge.Source).Concat(path.Select(edge => edge.Target)).Distinct().OrderBy(next => distObserver.Distances[next]));
}
}
// Create route tables
foreach (var source in FormMain.nodes)
source.routeTable = FormMain.nodes.ToDictionary(target => target, target =>
(
from edge in FormMain.edges
where edge.nodes.Contains(source)
let adjacent = edge.nodes[0] != source ? edge.nodes[0] : edge.nodes[1]
where !pathTable[adjacent.ID, target.ID].Contains(source.ID)
orderby edge.Weight + distanceTable[adjacent.ID, target.ID] ascending
select adjacent
).ToList());
TablesRequired = false;
}
public static void createTables()
{
// Create graph
var graph = new UndirectedGraph <int, Edge <int> >();
// Add vertices to the graph
for (var i = 0; i < FormMain.nodes.Count; i++)
{
graph.AddVertex(i);
}
// Create edges
var edgeCost = new Dictionary <Edge <int>, double>();
for (var i = 0; i < FormMain.edges.Count; i++)
{
var quickGraphEdge = new Edge <int>(FormMain.nodes.IndexOf(FormMain.edges[i].nodes[0]), FormMain.nodes.IndexOf(FormMain.edges[i].nodes[1]));
graph.AddEdge(quickGraphEdge);
edgeCost.Add(quickGraphEdge, FormMain.edges[i].Weight);
}
// Initialize tables
distanceTable = new double[FormMain.nodes.Count, FormMain.nodes.Count];
pathTable = new List <int> [FormMain.nodes.Count, FormMain.nodes.Count];
for (var i = 0; i < FormMain.nodes.Count; i++)
{
for (var j = 0; j < FormMain.nodes.Count; j++)
{
distanceTable[i, j] = double.PositiveInfinity;
pathTable[i, j] = new List <int>();
}
}
// Create tables
for (var source = 0; source < FormMain.nodes.Count; source++)
{
// We want to use Dijkstra on this graph
var dijkstra = new UndirectedDijkstraShortestPathAlgorithm <int, Edge <int> >(graph, edge => edgeCost[edge]);
// attach a distance observer to give us the shortest path distances
var distObserver = new UndirectedVertexDistanceRecorderObserver <int, Edge <int> >(edge => edgeCost[edge]);
distObserver.Attach(dijkstra);
// Attach a Vertex Predecessor Recorder Observer to give us the paths
var predecessorObserver = new UndirectedVertexPredecessorRecorderObserver <int, Edge <int> >();
predecessorObserver.Attach(dijkstra);
// Run the algorithm for current Node
dijkstra.Compute(source);
// Add values to table
foreach (var target in distObserver.Distances)
{
distanceTable[source, target.Key] = target.Value;
IEnumerable <Edge <int> > path;
if (predecessorObserver.TryGetPath(target.Key, out path))
{
pathTable[source, target.Key].AddRange(path.Select(edge => edge.Source).Concat(path.Select(edge => edge.Target)).Distinct().OrderBy(next => distObserver.Distances[next]));
}
}
}
// Create route tables
foreach (var source in FormMain.nodes)
{
source.routeTable = FormMain.nodes.ToDictionary(target => target, target =>
(
from edge in FormMain.edges
where edge.nodes.Contains(source)
let adjacent = edge.nodes[0] != source ? edge.nodes[0] : edge.nodes[1]
where !pathTable[adjacent.ID, target.ID].Contains(source.ID)
orderby edge.Weight + distanceTable[adjacent.ID, target.ID] ascending
select adjacent
).ToList());
}
TablesRequired = false;
}
