public PathFinderJob(
PathFinderJobSpec spec,
IEnumerable <byte[]> paths = null,
IDictionary <byte[], int> nodeCounts = null)
{
_name = spec.Name;
_tableau = spec.Tableau;
_startPoint = spec.StartPoint;
_endPoints = new HashSet <TerminalNode>(spec.EndPoints);
_threadCount = spec.ThreadCount;
_monitorInterval = spec.MonitorInterval;
_saveFilePath = Configuration.Filename(_tableau.Shape, _name);
_equivalentPathsLookup = _endPoints.ToDictionary(
endPoint => endPoint,
endPoint => _tableau.Shape.GetEquivalentPathsDelegate(new NodePair(_startPoint, endPoint)));
_paths = paths is not null
? new ConcurrentHashSet <byte[]>(paths, new ByteArrayEqualityComparer())
: new ConcurrentHashSet <byte[]>(new ByteArrayEqualityComparer());
_nodeCounts = nodeCounts is not null
? new ConcurrentDictionary <byte[], int>(nodeCounts, new ByteSequenceEqualEqualityComparer())
: new ConcurrentDictionary <byte[], int>(new ByteSequenceEqualEqualityComparer());
}
public static Dictionary <SymmetryType, int> GetSymmetries(this Tableau tableau, NodePair nodePair)
{
return(tableau.Shape.SymmetryTransformations
.Where(symmetry =>
nodePair.Node1.Coordinates == symmetry.Transform(nodePair.Node2.Coordinates) &&
nodePair.Node2.Coordinates == symmetry.Transform(nodePair.Node1.Coordinates))
.GroupBy(symmetry => symmetry.SymmetryType)
.ToDictionary(
group => group.Key,
group => group.Count()));
}
public static IEnumerable <NodePair> TerminalNodeCombinations(this Tableau tableau)
{
for (var i = 0; i < tableau.TerminalNodes.Count - 1; i++)
{
for (var j = i + 1; j < tableau.TerminalNodes.Count; j++)
{
yield return(new NodePair(
tableau.TerminalNodes[i],
tableau.TerminalNodes[j]));
}
}
}
/// <summary>
/// Considering the symmetry of the tableau, determine pairs of terminal nodes that are
/// distinct under the symmetry transformations.
/// </summary>
public static IEnumerable <NodePair> TerminalNodeUniqueCombinations(this Tableau tableau)
{
var symmetryTransformations = tableau.Shape.SymmetryTransformations;
var nodePairHashSet = new HashSet <NodePair>(NodePairCoordinatesEqualiyComparer.Default);
foreach (var nodePair in tableau.TerminalNodeCombinations())
{
var isEquivalentToExistingNodePair = symmetryTransformations
.Any(symmetry => nodePairHashSet.Contains(
new NodePair(
tableau[symmetry.Transform(nodePair.Node1.Coordinates)],
tableau[symmetry.Transform(nodePair.Node2.Coordinates)])));
if (!isEquivalentToExistingNodePair && nodePairHashSet.Add(nodePair))
{
yield return(nodePair);
}
}
}
