com.orientechnologies.orient.graph.sql.functions

Class OSQLFunctionAstar

java.lang.Object

com.orientechnologies.orient.core.sql.functions.OSQLFunctionAbstract

com.orientechnologies.orient.core.sql.functions.OSQLFunctionConfigurableAbstract

com.orientechnologies.orient.core.sql.functions.math.OSQLFunctionMathAbstract

com.orientechnologies.orient.graph.sql.functions.OSQLFunctionHeuristicPathFinderAbstract

com.orientechnologies.orient.graph.sql.functions.OSQLFunctionAstar

All Implemented Interfaces:

OSQLFunction

public class OSQLFunctionAstar
extends OSQLFunctionHeuristicPathFinderAbstract

A*'s algorithm describes how to find the cheapest path from one node to another node in a directed weighted graph with husrestic function.

The first parameter is source record. The second parameter is destination record. The third parameter is a name of property that represents 'weight' and fourth represnts the map of options.

If property is not defined in edge or is null, distance between vertexes are 0 .

Author:

Saeed Tabrizi (saeed a_t nowcando.com)

Field Summary

Fields

Modifier and Type	Field and Description
protected Map<OrientVertex,OrientVertex>	cameFrom
protected Set<OrientVertex>	closedSet
protected Map<OrientVertex,Double>	fScore
protected Map<OrientVertex,Double>	gScore
static String	NAME
protected PriorityQueue<OrientVertex>	open

Fields inherited from class com.orientechnologies.orient.graph.sql.functions.OSQLFunctionHeuristicPathFinderAbstract

context, db, MIN, PARAM_CUSTOM_HEURISTIC_FORMULA, PARAM_D_FACTOR, PARAM_DIRECTION, PARAM_EDGE_TYPE_NAMES, PARAM_EMPTY_IF_MAX_DEPTH, PARAM_HEURISTIC_FORMULA, PARAM_MAX_DEPTH, PARAM_PARALLEL, PARAM_TIE_BREAKER, PARAM_VERTEX_AXIS_NAMES, paramCustomHeuristicFormula, paramDestinationVertex, paramDFactor, paramDirection, paramEdgeTypeNames, paramEmptyIfMaxDepth, paramHeuristicFormula, paramMaxDepth, paramParallel, paramSourceVertex, paramTieBreaker, paramVertexAxisNames, rnd, route

Fields inherited from class com.orientechnologies.orient.core.sql.functions.OSQLFunctionConfigurableAbstract

configuredParameters

Fields inherited from class com.orientechnologies.orient.core.sql.functions.OSQLFunctionAbstract

maxParams, minParams, name

Constructor Summary

Constructors

Constructor and Description
OSQLFunctionAstar()

Method Summary

Modifier and Type	Method and Description
boolean	aggregateResults()
LinkedList<OrientVertex>	execute(Object iThis, OIdentifiable iCurrentRecord, Object iCurrentResult, Object[] iParams, OCommandContext iContext)
protected double	getDistance(OrientVertex node, OrientVertex parent, OrientVertex target)
protected double	getHeuristicCost(OrientVertex node, OrientVertex parent, OrientVertex target)
Object	getResult()
String	getSyntax()
protected boolean	isVariableEdgeWeight()

Methods inherited from class com.orientechnologies.orient.graph.sql.functions.OSQLFunctionHeuristicPathFinderAbstract

booleanOrDefault, doubleOrDefault, gcdist, getCustomHeuristicCost, getDiagonalHeuristicCost, getDiagonalHeuristicCost, getEuclideanHeuristicCost, getEuclideanHeuristicCost, getEuclideanNoSQRHeuristicCost, getEuclideanNoSQRHeuristicCost, getManhatanHeuristicCost, getManhatanHeuristicCost, getMaxAxisHeuristicCost, getMaxAxisHeuristicCost, getNeighbors, getPath, getSimpleHeuristicCost, getTieBreakingHeuristicCost, getTieBreakingHeuristicCost, getTieBreakingRandomHeuristicCost, integerOrDefault, longOrDefault, stringArray, stringOrDefault

Methods inherited from class com.orientechnologies.orient.core.sql.functions.math.OSQLFunctionMathAbstract

getClassWithMorePrecision, getContextValue, shouldMergeDistributedResult

Methods inherited from class com.orientechnologies.orient.core.sql.functions.OSQLFunctionConfigurableAbstract

config, toString

Methods inherited from class com.orientechnologies.orient.core.sql.functions.OSQLFunctionAbstract

filterResult, getDistributedStorageId, getMaxParams, getMinParams, getName, mergeDistributedResult, returnDistributedResult, setResult

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

NAME

public static final String NAME

See Also:

Constant Field Values

closedSet

protected Set<OrientVertex> closedSet

cameFrom

protected Map<OrientVertex,OrientVertex> cameFrom

gScore

protected Map<OrientVertex,Double> gScore

fScore

protected Map<OrientVertex,Double> fScore

open

protected PriorityQueue<OrientVertex> open

Constructor Detail

OSQLFunctionAstar

public OSQLFunctionAstar()

Method Detail

execute

public LinkedList<OrientVertex> execute(Object iThis,
                                        OIdentifiable iCurrentRecord,
                                        Object iCurrentResult,
                                        Object[] iParams,
                                        OCommandContext iContext)

getSyntax

public String getSyntax()

getResult

public Object getResult()

Specified by:

getResult in interface OSQLFunction

Overrides:

getResult in class OSQLFunctionAbstract

getDistance

protected double getDistance(OrientVertex node,
                             OrientVertex parent,
                             OrientVertex target)

Specified by:

getDistance in class OSQLFunctionHeuristicPathFinderAbstract

aggregateResults

public boolean aggregateResults()

Specified by:

aggregateResults in interface OSQLFunction

Overrides:

aggregateResults in class OSQLFunctionMathAbstract

getHeuristicCost

protected double getHeuristicCost(OrientVertex node,
                                  OrientVertex parent,
                                  OrientVertex target)

Specified by:

getHeuristicCost in class OSQLFunctionHeuristicPathFinderAbstract

isVariableEdgeWeight

protected boolean isVariableEdgeWeight()

Overrides:

isVariableEdgeWeight in class OSQLFunctionHeuristicPathFinderAbstract