Calculates the transitive closure for a directed acyclic graph.
Remarks
Let G = (V, E) be a directed acyclic graph. The transitive closure of G is a graph which contains an edge (v, w) (with v ≠ w) only if there exists a path from v to w in G. This implementation produces the transitive closure and not the reflexive, transitive closure of the specified graph, since no representations for self-loops are added.
Other Transitivity Algorithms
yFiles for HTML supports other algorithms related to transitivity:
- TransitiveEdges – calculates the edges which connect the visible nodes in a graph if these are indirectly connected via hidden nodes.
- TransitiveReduction – calculates the transitive reduction of a graph, i.e. the edges that are unnecessary to only ensure that the same reachability relation is represented
Examples
// prepare the transitive closure algorithm
const algorithm = new TransitiveClosure()
// run the algorithm
const result = algorithm.run(graph)
// Add the edges in the closure with a different style
for (const edge of result.edgesToAdd) {
graph.createEdge(edge.source, edge.target, transitiveEdgeStyle)
}Type Details
- yfiles module
- view-layout-bridge
- yfiles-umd modules
- view-layout-bridge
- Legacy UMD name
- yfiles.analysis.TransitiveClosure
See Also
Constructors
Creates a new TransitiveClosure instance.
Parameters
A map of options to pass to the method.
- subgraphNodes - ItemCollection<INode>
The collection of nodes which define a subset of the graph for the algorithms to work on. This option sets the subgraphNodes property on the created object.
- subgraphEdges - ItemCollection<IEdge>
The collection of edges which define a subset of the graph for the algorithms to work on. This option sets the subgraphEdges property on the created object.
Properties
Gets or sets the collection of edges which define a subset of the graph for the algorithms to work on.
Remarks
If nothing is set, all edges of the graph will be processed.
If only the excludes are set all edges in the graph except those provided in the excludes are processed.
Note that edges which start or end at nodes which are not in the subgraphNodes are automatically not considered by the algorithm.
ItemCollection<T> instances may be shared among algorithm instances and will be (re-)evaluated upon (re-)execution of the algorithm.
Examples
// prepare the transitive closure algorithm
const algorithm = new TransitiveClosure({
// Ignore edges without target arrow heads
subgraphEdges: {
excludes: (edge) =>
edge.style instanceof PolylineEdgeStyle &&
edge.style.targetArrow === IArrow.NONE
}
})
// run the algorithm
const result = algorithm.run(graph)
// Add the edges in the closure with a different style
for (const edge of result.edgesToAdd) {
graph.createEdge(edge.source, edge.target, transitiveEdgeStyle)
}// prepare the transitive closure algorithm
const algorithm = new TransitiveClosure({
// Ignore edges without target arrow heads
subgraphEdges: {
excludes: (edge: IEdge): boolean =>
edge.style instanceof PolylineEdgeStyle &&
edge.style.targetArrow === IArrow.NONE
}
})
// run the algorithm
const result = algorithm.run(graph)
// Add the edges in the closure with a different style
for (const edge of result.edgesToAdd) {
graph.createEdge(edge.source, edge.target, transitiveEdgeStyle)
}Gets or sets the collection of nodes which define a subset of the graph for the algorithms to work on.
Remarks
If nothing is set, all nodes of the graph will be processed.
If only the excludes are set all nodes in the graph except those provided in the excludes are processed.
ItemCollection<T> instances may be shared among algorithm instances and will be (re-)evaluated upon (re-)execution of the algorithm.
Examples
// prepare the transitive closure algorithm
const algorithm = new TransitiveClosure({
subgraphNodes: {
// only consider elliptical nodes in the graph
includes: (node) =>
node.style instanceof ShapeNodeStyle &&
node.style.shape === ShapeNodeShape.ELLIPSE,
// but ignore the first node, regardless of its shape
excludes: graph.nodes.first()
}
})
// run the algorithm
const result = algorithm.run(graph)
// Add the edges in the closure with a different style
for (const edge of result.edgesToAdd) {
graph.createEdge(edge.source, edge.target, transitiveEdgeStyle)
}// prepare the transitive closure algorithm
const algorithm = new TransitiveClosure({
subgraphNodes: {
// only consider elliptical nodes in the graph
includes: (node: INode): boolean =>
node.style instanceof ShapeNodeStyle &&
node.style.shape === ShapeNodeShape.ELLIPSE,
// but ignore the first node, regardless of its shape
excludes: graph.nodes.first()
}
})
// run the algorithm
const result = algorithm.run(graph)
// Add the edges in the closure with a different style
for (const edge of result.edgesToAdd) {
graph.createEdge(edge.source, edge.target, transitiveEdgeStyle)
}Methods
Calculates the transitive closure for a directed acyclic graph.
Preconditions
- The graph must be
.
Parameters
A map of options to pass to the method.
- graph - IGraph
- The input graph to run the algorithm on.
Returns
- ↪TransitiveClosureResult
- A TransitiveClosureResult containing placeholders for edges that can be inserted to obtain the transitive closure of
graph.
Throws
- Exception({ name: 'InvalidOperationError' })
- If the algorithm can't create a valid result due to an invalid graph structure or wrongly configured properties.