drasys.or.graph.vrp
Class Randomizer

java.lang.Object
  |
  +--drasys.or.graph.vrp.Randomizer

Direct Known Subclasses:

ClarkeWright, GillettMiller

public class Randomizer

extends java.lang.Object

implements ConstructI

A class to randomize VRP algorithms that implement 'Randomizable'.

Constructor Summary

Randomizer(RandomizableI randomizable)           Constructs a Randomizer to operate on the algorithm 'randomizable'.

 

Method Summary
void	addIterations(int count, int strength)           Adds a sequence of iterations at a given strength value.
double	constructClosedTours(java.lang.Object depotKey)           Construct a solution with closed tours that begin and end at the depot vertex.
double	constructInboundTours(java.lang.Object depotKey)           Construct a solution with open tours that begin at arbitrary vertices and end at the depot vertex.
double	constructOutboundTours(java.lang.Object depotKey)           Construct a solution with open tours that begin at the depot vertex and end at arbitrary vertices.
double	getCost()           Returns the total cost of the solution tours.
double[]	getCosts()           Returns the cost of each tour in the solution.
double[]	getLoads()           Returns the load for each tour in the solution.
RandomI	getRandom()           Gets the random number generator.
java.util.Vector[]	getTours()           Returns the improved tour from the construction algorithm.
void	selectVertex(boolean select)           Selects all of the vertices in the graph to be in the solution if 'select' is true.
void	selectVertex(boolean[] select)           Selects all of the vertices whose corresponding element in 'select' is true.
void	selectVertex(java.lang.Object key, boolean select)           Selects the vertex to be in the solution if 'select' is true.
void	setCapacityConstraint(double maxLoadPerVehicle)           Sets the vehicle capacity constraint.
void	setCostConstraint(double maxCostPerVehicle)           Sets the vehicle cost constraint.
void	setEdgeKey(java.lang.Object edgeKey)           Sets the key used to select from parallel edges between vertices.
void	setGraph(GraphI graph)           Sets the graph for the VRP algorithm.
void	setProperties(PropertiesI properties)           Sets the properties object.
void	setRandom(RandomI random)           Sets the random number generator.
void	setVehicleCost(double vehicleCost)           Sets the vehicle cost constraint.

 

Methods inherited from class java.lang.Object

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

 

Constructor Detail

Randomizer

public Randomizer(RandomizableI randomizable)
           throws VRPException

Constructs a Randomizer to operate on the algorithm 'randomizable'.

Throws:

VRPException - if 'randomizable' does not implement 'ConstructI' or 'ImproveI'.

addIterations

public void addIterations(int count,
                          int strength)

Adds a sequence of iterations at a given strength value.

setRandom

public void setRandom(RandomI random)

Sets the random number generator.

getRandom

public RandomI getRandom()

Gets the random number generator.

selectVertex

public void selectVertex(boolean[] select)

Selects all of the vertices whose corresponding element in 'select' is true. Unselects all of the vertices whose corresponding element in 'select' is false. All of the vertices are selected by default when the algorithm is constructed.

Specified by:

selectVertex in interface ConstructI

selectVertex

public void selectVertex(boolean select)

Selects all of the vertices in the graph to be in the solution if 'select' is true. Unselects all of the vertices if 'select' is false. All of the vertices are selected by default when the algorithm is constructed.

Specified by:

selectVertex in interface ConstructI

selectVertex

public void selectVertex(java.lang.Object key,
                         boolean select)
                  throws VertexNotFoundException

Selects the vertex to be in the solution if 'select' is true. Unselects the vertex if 'select' is false. All of the vertices are selected by default when the algorithm is constructed.

Specified by:

selectVertex in interface ConstructI

constructOutboundTours

public double constructOutboundTours(java.lang.Object depotKey)
                              throws SolutionNotFoundException,
                                     VertexNotFoundException

Construct a solution with open tours that begin at the depot vertex and end at arbitrary vertices.

Specified by:

constructOutboundTours in interface ConstructI

Throws:

SolutionNotFoundException - if a solution can not be constructed.

constructInboundTours

public double constructInboundTours(java.lang.Object depotKey)
                             throws SolutionNotFoundException,
                                    VertexNotFoundException

Construct a solution with open tours that begin at arbitrary vertices and end at the depot vertex.

Specified by:

constructInboundTours in interface ConstructI

Throws:

SolutionNotFoundException - if a solution can not be constructed.

constructClosedTours

public double constructClosedTours(java.lang.Object depotKey)
                            throws SolutionNotFoundException,
                                   VertexNotFoundException

Construct a solution with closed tours that begin and end at the depot vertex.

Specified by:

constructClosedTours in interface ConstructI

Throws:

SolutionNotFoundException - if a solution can not be constructed.

setGraph

public void setGraph(GraphI graph)

Sets the graph for the VRP algorithm.

setVehicleCost

public void setVehicleCost(double vehicleCost)

Sets the vehicle cost constraint. The units must be the same as the edge traversal costs.

setCostConstraint

public void setCostConstraint(double maxCostPerVehicle)

Sets the vehicle cost constraint.

setCapacityConstraint

public void setCapacityConstraint(double maxLoadPerVehicle)

Sets the vehicle capacity constraint.

setProperties

public void setProperties(PropertiesI properties)

Sets the properties object.

setEdgeKey

public void setEdgeKey(java.lang.Object edgeKey)

Sets the key used to select from parallel edges between vertices. The default value for 'edgeKey' is null.

getTours

public java.util.Vector[] getTours()
                            throws SolutionNotFoundException

Returns the improved tour from the construction algorithm. The vector contains all the edges and the vertices in alternating order starting and ending with a vertex. The elements will always be arranged in the order of forward tour traversal.

Throws:

SolutionNotFoundException - if no solution was created.

getCost

public double getCost()
               throws SolutionNotFoundException

Returns the total cost of the solution tours.

Throws:

SolutionNotFoundException - if no solution was created.

getCosts

public double[] getCosts()
                  throws SolutionNotFoundException

Returns the cost of each tour in the solution.

Throws:

SolutionNotFoundException - if no solution was created.

getLoads

public double[] getLoads()
                  throws SolutionNotFoundException

Returns the load for each tour in the solution.

Throws:

SolutionNotFoundException - if no solution was created.