This class can be used to solve the problem of finding strongly connected components in a directed graph. More...
Instance Methods | |
| (id) | - initWithSession: |
| Creates a new instance of StrongConnectivityGabow. More... | |
| (void) | - run |
| Executes the algorithm. | |
| (void) | - addEdgeType:dir: |
| Allows connectivity through edges of the given type. More... | |
| (void) | - addAllEdgeTypes: |
| Allows connectivity through all edge types of the graph. More... | |
| (void) | - addNodeType: |
| Allows connectivity through nodes of the given type. More... | |
| (void) | - addAllNodeTypes |
| Allows connectivity through all node types of the graph. | |
| (void) | - excludeNodes: |
| Set which nodes can't be used. More... | |
| (void) | - excludeEdges: |
| Set which edges can't be used. More... | |
| (STSConnectedComponents *) | - getConnectedComponents |
| Returns the results generated by the execution of the algorithm. More... | |
| (void) | - setMaterializedAttribute: |
| Creates a new common attribute type for all node types in the graph in order to store, persistently, the results related to the connected components found while executing this algorithm. More... | |
| (void) | - close |
| Closes the Connectivity instance. More... | |
| (BOOL) | - isClosed |
| Check if the Connectivity instance is closed. | |
Detailed Description
This class can be used to solve the problem of finding strongly connected components in a directed graph.
It consists in finding components where every pair (u,v) of nodes contained in it has a path from u to v using the specified direction for each edge type. This implementation is based on the Gabow algorithm.
It is possible to set some restrictions after constructing a new instance of this class and before running it in order to limit the results.
After the execution, we can retrieve the results stored in an instance of the ConnectedComponents class using the GetConnectedComponents method.
Check out the 'Algorithms' section in the SPARKSEE User Manual for more details on this.
Method Documentation
| - (void) addAllEdgeTypes: | (enum STSEdgesDirection) | dir |
Allows connectivity through all edge types of the graph.
- Parameters
-
dir [in] Edge direction.
| - (void) addEdgeType: | (int) | type | |
| dir: | (enum STSEdgesDirection) | dir | |
Allows connectivity through edges of the given type.
- Parameters
-
type [in] Edge type. dir [in] Edge direction.
| - (void) addNodeType: | (int) | t |
Allows connectivity through nodes of the given type.
- Parameters
-
t null
| - (void) close |
Closes the Connectivity instance.
It must be called to ensure the integrity of all data.
| - (void) excludeEdges: | (STSObjects *) | edges |
Set which edges can't be used.
This will replace any previously specified set of excluded edges. Should only be used to exclude the usage of specific edges from allowed edge types because it's less efficient than not allowing an edge type.
- Parameters
-
edges [in] A set of edge identifiers that must be kept intact until the destruction of the class.
| - (void) excludeNodes: | (STSObjects *) | nodes |
Set which nodes can't be used.
This will replace any previously specified set of excluded nodes. Should only be used to exclude the usage of specific nodes from allowed node types because it's less efficient than not allowing a node type.
- Parameters
-
nodes [in] A set of node identifiers that must be kept intact until the destruction of the class.
| - (STSConnectedComponents*) getConnectedComponents |
Returns the results generated by the execution of the algorithm.
These results contain information related to the connected components found as the number of different components, the set of nodes contained in each component or many other data.
- Returns
- Returns an instance of the class ConnectedComponents which contain information related to the connected components found.
| - (id) initWithSession: | (STSSession *) | session |
Creates a new instance of StrongConnectivityGabow.
After creating this instance is required to indicate the set of edge types and the set of node types which will be navigated through while traversing the graph in order to find the strong connected components.
- Parameters
-
session [in] Session to get the graph from and calculate the connectivity
| - (void) setMaterializedAttribute: | (NSString *) | attributeName |
Creates a new common attribute type for all node types in the graph in order to store, persistently, the results related to the connected components found while executing this algorithm.
Whenever the user wants to retrieve the results, even when the graph has been closed and opened again, it is only necessary to create a new instance of the class ConnectedComponents indicating the graph and the name of the common attribute type which stores the results. This instance will have all the information related to the connected components found in the moment of the execution of the algorithm that stored this data.
It is possible to run the algorithm without specifying this parameter in order to avoid materializing the results of the execution.
- Parameters
-
attributeName [in] The name of the common attribute type for all node types in the graph which will store persistently the results generated by the execution of the algorithm.
The documentation for this class was generated from the following file:
- Sparksee.h
