SinglePairShortestPathDijkstra class. More...

Inheritance diagram for STSSinglePairShortestPathDijkstra:

Collaboration diagram for STSSinglePairShortestPathDijkstra:

Instance Methods
(void)	- run
	Executes the algorithm.

(STSOidList *)	- getPathAsNodes
	Gets the shortest path between the source node and the destination node as an ordered set of nodes. More...

(STSOidList *)	- getPathAsEdges
	Gets the shortest path between the source node and the destination node as an ordered set of edges. More...

(double)	- getCost
	Gets the cost of the shortest path. More...

(id)	- initWithSession:src:dst:
	Creates a new instance. More...

(void)	- addWeightedEdgeType:dir:attr:
	Allows for traversing edges of the given type using the given attribute as the weight. More...

(void)	- setUnweightedEdgeCost:
	Sets the weight assigned to the unweighted edges. More...

(void)	- setDynamicEdgeCostCallback:
	Set a class callback to dynamically calculate the cost of the edges. More...

(BOOL)	- exists
	Returns TRUE If a path exists or FALSE otherwise.

(void)	- setMaximumHops:
	Sets the maximum hops restriction. More...

(void)	- addEdgeType:dir:
	Allows for traversing edges of the given type. More...

(void)	- addAllEdgeTypes:
	Allows for traversing all edge types of the graph. More...

(void)	- addNodeType:
	Allows for traversing nodes of the given type. More...

(void)	- addAllNodeTypes
	Allows for traversing 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...

(void)	- close
	Closes the ShortestPath instance. More...

(BOOL)	- isClosed
	Check if the ShortestPath instance is closed.

Detailed Description

SinglePairShortestPathDijkstra class.

It solves the single-pair shortest path problem using a Dijkstra-based implementation.

It is a weighted algorithm, so it takes into account the cost of the edges to compute a minimum-cost shortest path. That is, the user may set for each edge type which attribute should be used to retrieve the cost of the edge. If no attribute is given for an edge type, this will assume the edge has a fixed cost (the default is 1). Only numerical attribute can be set as weight attributes (that is Long, Integer or Double attributes are allowed).

Check out the 'Algorithms' section in the SPARKSEE User Manual for more details on this.

Author: Sparsity Technologies http://www.sparsity-technologies.com

Method Documentation

- (void) addAllEdgeTypes: (enum STSEdgesDirection) dir

Allows for traversing all edge types of the graph.

Parameters

dir	[in] Edge direction.

- (void) addEdgeType:	(int)	type
dir:	(enum STSEdgesDirection)	dir

Allows for traversing edges of the given type.

Parameters

type	[in] Edge type.
dir	[in] Edge direction.

- (void) addNodeType: (int) type

Allows for traversing nodes of the given type.

Parameters

type null

- (void) addWeightedEdgeType:	(int)	type
dir:	(enum STSEdgesDirection)	dir
attr:	(int)	attr

Allows for traversing edges of the given type using the given attribute as the weight.

Parameters

type	[in] Edge type.
dir	[in] Edge direction.
attr	[in] Attribute to be used as the weight. It must be a global attribute or an attribute of the given edge type.

- (void) close

Closes the ShortestPath 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.

- (double) getCost

Gets the cost of the shortest path.

The cost is the sum of the weights of the edges in the shortest path.

Returns: The cost of the shortest path.

Implements STSSinglePairShortestPath.

- (STSOidList*) getPathAsEdges

Gets the shortest path between the source node and the destination node as an ordered set of edges.

Returns: Ordered set of edge identifiers.

Implements STSSinglePairShortestPath.

- (STSOidList*) getPathAsNodes

Gets the shortest path between the source node and the destination node as an ordered set of nodes.

Returns: Ordered set of node identifiers.

Implements STSSinglePairShortestPath.

- (id) initWithSession:	(STSSession *)	session
src:	(long long)	src
dst:	(long long)	dst

Creates a new instance.

Parameters

session	[in] Session to get the graph from and perform traversal.
src	[in] Source node.
dst	[dst] Destination node.

- (void) setDynamicEdgeCostCallback: (STSSinglePairShortestPathDijkstraDynamicCost *) dynCostCalculator

Set a class callback to dynamically calculate the cost of the edges.

The callback can be set to NULL (the default) to use the normal attribute based cost weights. The given class must be kept alive by the user for as long as the algorithm is running.

Parameters

dynCostCalculator [in] Class callback to calculate the edge costs

- (void) setMaximumHops: (int) maxhops

Sets the maximum hops restriction.

All paths longer than the maximum hops restriction will be ignored.

Parameters

maxhops [in] The maximum hops restriction. It must be positive or zero. Zero, the default value, means unlimited.

- (void) setUnweightedEdgeCost: (double) weight

Sets the weight assigned to the unweighted edges.

All the edges from the types added without an explicit weight attribute will get this weight. The default weight for this edges is 1.

Parameters

weight [in] The weight value for unweighted edges.

The documentation for this class was generated from the following file:

Sparksee.h

Instance Methods

Detailed Description

Method Documentation