/// <summary>
/// Build a List of Columns from a PetriNet
/// </summary>
/// <param name="petriNet"></param>
/// <returns></returns>
/// <author>Jannik Arndt</author>
public static List <Column> Build(PetriNet petriNet)
{
// Initialize
GlobalColumnList.Clear();
Column firstColumn = new Column(0);
Place startPlace = (Place)petriNet.GetSources()[0];
firstColumn.HashSetOfNodes.Add(startPlace);
GlobalColumnList.Add(firstColumn);
// Recursively add all columns
AddPlace(startPlace, 1);
// Correct the end-place
Place endPlace = (Place)petriNet.GetSinks()[0];
Column temp = FindNode(endPlace);
if (temp != null && temp.ColumnNumber < GlobalColumnList.Count)
{
temp.HashSetOfNodes.Remove(endPlace);
TrimGlobalColumnList();
GetOrCreateColumn(GlobalColumnList.Count).HashSetOfNodes.Add(endPlace);
}
return(GlobalColumnList);
}
/// <summary>
/// Remove old "End"-Places, combine sinks and add new "End"-Place
/// </summary>
/// <param name="petriNet">The petrinet to work on</param>
/// <author>Jannik Arndt</author>
public void FixEnding(PetriNet petriNet)
{
foreach (Place endPlace in petriNet.Places.Where(place => place.Name.Equals("End")))
{
endPlace.Name = "";
}
List <Place> endPlaces = (from sink in petriNet.GetSinks() where sink.GetType() == typeof(Place) select sink as Place).ToList();
if (endPlaces.Count > 1)
{
foreach (Place endPlace in endPlaces.Skip(1))
{
foreach (Transition incomingTransition in endPlace.IncomingTransitions)
{
endPlaces[0].IncomingTransitions.Add(incomingTransition);
incomingTransition.OutgoingPlaces.Clear();
incomingTransition.OutgoingPlaces.Add(endPlaces[0]);
}
petriNet.Places.Remove(endPlace);
}
}
endPlaces[0].Name = "End";
}
/// <summary>
/// Goes through the steps of the (improved) HeuristicMiner Algorithm:
/// Find starting-events => build adjacency-matrix => convert into petrinet
/// </summary>
/// <returns>A PetriNet as a ProcessModel</returns>
/// <exception cref="ArgumentNullException">If the field-parameter is null.</exception>
/// <author>Jannik Arndt</author>
public ProcessModel Mine()
{
if (_field == null)
{
throw new Exception("The field parameter was null");
}
// Get parameters from MinerSettings
var threshold = MinerSettings.GetAsDouble("AdjacencyThresholdSlider") / 100;
var maxDepth = MinerSettings.GetAsInt("MaximumRecursionDepthSlider");
if (threshold < 0 || threshold > 1)
{
throw new Exception("Threshold must be between 0 and 1.");
}
if (maxDepth < 1)
{
throw new Exception("Maximum recursion depth must be more greater than 1.");
}
// Statistics
var processingTimeStart = Process.GetCurrentProcess().TotalProcessorTime;
// 1. Create Adjacency Matrix
var adjacencyMatrix = CreateAdjacencyMatrix(_field);
// 2. Calculate the indexes of the first events
var startindexes = GetColumnsWithOnlyNegativeEntries(adjacencyMatrix);
// for every sub-processmodel
foreach (var startindex in startindexes)
{
// 3. Create the dependency-Graph
var rootNode = CreateDependencyGraph(_field.EventLog.ListOfUniqueEvents, adjacencyMatrix, threshold, 0.0, startindex, maxDepth);
// 4. Turn the dependency-graph into a petri-net
_listOfSubPetriNets.Add(CreatePetriNetFromDependencyGraph(rootNode, _field.EventLog, _field.Infotext));
}
// 5. Connect all Petrinets by one XOR-Split
if (_listOfSubPetriNets.Count > 1)
{
// 5a. Connect all subnets to one start
var startingPlace = _finalPetriNet.AddPlace("Start");
foreach (var petriNet in _listOfSubPetriNets)
{
var xorTransition = _finalPetriNet.AddTransition(incomingPlace: startingPlace);
_finalPetriNet.MergeWithPetriNet(petriNet, xorTransition);
}
// 5b. Add following transitions to all subnet-endings
foreach (var openEndPlace in _finalPetriNet.GetSinks())
{
if (openEndPlace.GetType() == typeof(Place))
{
_finalPetriNet.AddTransition(incomingPlace: (Place)openEndPlace);
}
}
}
else
{
_finalPetriNet = _listOfSubPetriNets[0];
}
// 6. Connect all open endings
_finalPetriNet = FixEnding(_finalPetriNet);
// 7. Delete empty transitions
_finalPetriNet = PetriNetOperation.CleanUpPetriNet(_finalPetriNet);
// 8. Save information about the mining-process
var processingTimeEnd = Process.GetCurrentProcess().TotalProcessorTime;
var processingTime = Math.Abs((processingTimeEnd - processingTimeStart).TotalMilliseconds) < 1 ? "< 15 ms" : (processingTimeEnd - processingTimeStart).TotalMilliseconds + " ms";
_field.Information.Add("Processing Time", processingTime);
_field.Information.Add("Number of Events", _finalPetriNet.Transitions.Count(s => s.IsLoop == false).ToString(CultureInfo.InvariantCulture));
_field.Information.Add("Number of Transitions", _finalPetriNet.Transitions.Count.ToString(CultureInfo.InvariantCulture));
_field.Information.Add("Number of Places", _finalPetriNet.Places.Count.ToString(CultureInfo.InvariantCulture));
_field.Information.Add("Loops in the net", _finalPetriNet.CountLoops().ToString(CultureInfo.InvariantCulture));
_field.Information.Add("Events used", _finalPetriNet.CountTransitionsWithoutANDs() - _finalPetriNet.CountLoops() + " of " + _field.EventLog.ListOfUniqueEvents.Count);
_field.Information.Add("Parallel Models", startindexes.Count.ToString(CultureInfo.InvariantCulture));
if (_listOfNodes.Count > 0)
{
_field.Information.Add("Minimal Adjacency", _listOfNodes.Min().ToString(CultureInfo.InvariantCulture));
_field.Information.Add("Average Adjacency", Math.Round(_listOfNodes.Average(), 3).ToString(CultureInfo.InvariantCulture));
if (Math.Abs(_listOfNodes.Min() - _listOfNodes.Average()) > 0.0001)
{
_field.Information.Add("Standard Deviation", CalculateStandardDeviation(_listOfNodes).ToString(CultureInfo.InvariantCulture));
}
}
return(_finalPetriNet);
}
