Section: Visualization Toolkit Filtering Classes
The distributed graph helper provides facilities used by vtkGraph to communicate with other processors that store other parts of the same distributed graph. The only user-level functionality provided by vtkDistributedGraphHelper involves this communication among processors and the ability to map between "distributed" vertex and edge IDs and their component parts (processor and local index). For example, the Synchronize() method provides a barrier that allows all processors to catch up to the same point in the code before any processor can leave that Synchronize() call. For example, one would call Synchronize() after adding many edges to a distributed graph, so that all processors can handle the addition of inter-processor edges and continue, after the Synchronize() call, with a consistent view of the distributed graph. For more information about manipulating (distributed) graphs, see the vtkGraph documentation.
To create an instance of class vtkDistributedGraphHelper, simply invoke its constructor as follows
obj = vtkDistributedGraphHelper
obj
is an instance of the vtkDistributedGraphHelper class.
string = obj.GetClassName ()
int = obj.IsA (string name)
vtkDistributedGraphHelper = obj.NewInstance ()
vtkDistributedGraphHelper = obj.SafeDownCast (vtkObject o)
vtkIdType = obj.GetVertexOwner (vtkIdType v) const
- Returns owner of vertex v, by extracting top ceil(log2 P) bits of v.
vtkIdType = obj.GetVertexIndex (vtkIdType v) const
- Returns local index of vertex v, by masking off top ceil(log2 P) bits of v.
vtkIdType = obj.GetEdgeOwner (vtkIdType e_id) const
- Returns owner of edge with ID e_id, by extracting top ceil(log2 P) bits of e_id.
vtkIdType = obj.GetEdgeIndex (vtkIdType e_id) const
- Returns local index of edge with ID e_id, by masking off top ceil(log2 P)
bits of e_id.
vtkIdType = obj.MakeDistributedId (int owner, vtkIdType local)
- Builds a distributed ID consisting of the given owner and the local ID.
obj.Synchronize ()
- Synchronizes all of the processors involved in this distributed
graph, so that all processors have a consistent view of the
distributed graph for the computation that follows. This routine
should be invoked after adding new edges into the distributed
graph, so that other processors will see those edges (or their
corresponding back-edges).
vtkDistributedGraphHelper = obj.Clone ()
- Clones the distributed graph helper, returning another
distributed graph helper of the same kind that can be used in
another vtkGraph.