Hi,

If the type of your probability table is serializable, you can assign the table to the node's Tag property and it will be serialized automatically. However the data will be saved as base64-encoded string inside the <Tag> element instead of human-readable xml. If you prefer the latter, you can handle the SerializeTag and DeserializeTag events to create any XML elements you'd like.

You can also create a custom node type and override its SaveToXml and LoadFromXml methods. In the methods' implementation you can either use the .NET's Xml classes to create new elements under the one provided as argument, or use the helper methods from the XmlContext argument to create an element and set its data with a single method call. You can see this done in the "Scripting" sample project.

I hope that helps,
Stoyan

Try this for parent nodes:
DiagramItemCollection items = diagram.ActiveItem.Query("inlinks/origin");

and for grandparents:
DiagramItemCollection items = diagram.ActiveItem.Query("inlinks/origin/inlinks/origin");

I hope that helps,
Stoyan

This will return all nodes up in the graph:

Function GetPredecessors(ByVal node As DiagramNode) As List(Of DiagramNode)
	Dim predecessors As New List(Of DiagramNode)

	' run breadth-first search trough this queue
	Dim queue As New Queue(Of DiagramNode)
	queue.Enqueue(node)

	While queue.Count > 0
		Dim pred As DiagramNode = queue.Dequeue
		If Not predecessors.Contains(pred) Then
			predecessors.Add(pred)
			For Each parent As DiagramNode In pred.Query("inlinks/origin")
				queue.Enqueue(parent)
			Next
		End If
	End While

	' remove the argument node
	predecessors.RemoveAt(0)

	Return predecessors
End Function 

I hope that helps,
Stoyan