net.sf.cpsolver.ifs.model
Class Model

java.lang.Object
  net.sf.cpsolver.ifs.model.Model

Direct Known Subclasses:

ConstantModel, CSPModel, ExamModel, JobShopModel, MultiModel, RPPModel, StructuredCSPModel, StudentSctBBTest, StudentSectioningModel, TimetableModel

public class Model
extends Object

Generic model (definition of a problem).

It consists of variables and constraints. It has also capability of memorizing the current and the best ever found assignment.

Example usage:

MyModel model = new MyModel();
Variable a = new MyVariable("A");
model.addVariable(a);
Variable b = new MyVariable("B");
model.addVariable(b);
Variable c = new MyVariable("C");
model.addVariable(c);
Constraint constr = MyConstraint("all-different");
model.addConstraint(constr);
constr.addVariable(a);
constr.addVariable(b);
constr.addVariable(c);
solver.setInitialSolution(model);

Version:

IFS 1.1 (Iterative Forward Search)
Copyright (C) 2006 Tomáš Müller
muller@unitime.org
Lazenska 391, 76314 Zlin, Czech Republic

This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

See Also:

Variable, Constraint, Solution, Solver

Field Summary

protected EnumerableCollection	iAssignedVariables
protected EnumerableCollection	iPerturbVariables
protected EnumerableCollection	iUnassignedVariables
protected static DecimalFormat	sDoubleFormat
protected static DecimalFormat	sPercentageFormat
protected static DecimalFormat	sTimeFormat

Constructor Summary

Model()
Constructor

Method Summary

void	addConstraint(Constraint constraint) Adds a constraint to the model
void	addGlobalConstraint(GlobalConstraint constraint) Adds a global constraint to the model
void	addModelListener(ModelListener listener) Adds a model listener
void	addVariable(Variable variable) Adds a variable to the model
void	afterAssigned(long iteration, Value value) Called after a value is assigned to its variable
void	afterUnassigned(long iteration, Value value) Called after a value is unassigned from its variable
EnumerableCollection	assignedVariables() The list of assigned variables in the model
void	beforeAssigned(long iteration, Value value) Called before a value is assigned to its variable
void	beforeUnassigned(long iteration, Value value) Called before a value is unassigned from its variable
EnumerableCollection	bestUnassignedVariables() The list of unassigned variables in the best ever found solution
void	clearBest() Clear the best ever found assignment
Hashtable	conflictConstraints(Value value) The list of constraints which are in a conflict with the given value if it is assigned to its variable.
Set	conflictValues(Value value) Returns the set of confliction variables with this value, if it is assigned to its variable
Vector	constraints() The list of constraints in the model
int	countConstraints() The number of constraints in the model
int	countGlobalConstraints() The number of global constraints in the model
int	countVariables() The number of variables in the model
int	getBestPerturbations() Returns the number of perturbation variables in the best ever found solution
int	getBestUnassignedVariables() Returns the number of unassigned variables in the best ever found solution
Hashtable	getExtendedInfo() Extended information about current solution.
Hashtable	getInfo() Returns information about the current solution.
Hashtable	getInfo(Vector variables) Returns information about the current solution.
protected Vector	getInfoProviders() Registered info providers (see InfoProvider)
Vector	getModelListeners() The list of model listeners
protected String	getPerc(double value, double min, double max)
protected String	getPercRev(double value, double min, double max)
double	getTotalValue() Value of the current solution.
double	getTotalValue(Vector variables) Value of the current solution.
Vector	globalConstraints() The list of global constraints in the model
boolean	inConflict(Value value) Return true if the given value is in conflict with a hard constraint
boolean	init(Solver solver) Model initialization
protected void	invalidateVariablesWithInitialValueCache() Invalidates cache containing all variables that possess an initial value
ModelListener	modelListenerOfType(Class type) The list of model listeners that are of the given class
int	nrAssignedVariables() Number of assigned variables
int	nrUnassignedVariables() Number of unassigned variables
EnumerableCollection	perturbVariables() The list of perturbation variables in the model, i.e., the variables which has an initial value but which are not assigned with this value.
EnumerableCollection	perturbVariables(Vector variables) The list of perturbation variables in the model, i.e., the variables which has an initial value but which are not assigned with this value.
void	removeConstraint(Constraint constraint) Removes a constraint from the model
void	removeGlobalConstraint(GlobalConstraint constraint) Removes a global constraint from the model
void	removeModelListener(ModelListener listener) Removes a model listener
void	removeVariable(Variable variable) Removes a variable from the model
void	restoreBest() Restore the best ever found assignment into the current assignment
void	saveBest() Save the current assignment as the best ever found assignment
String	toString()
Vector	unassignedHardConstraints() The list of hard constraints which contain at least one variable that is not assigned.
EnumerableCollection	unassignedVariables() The list of unassigned variables in the model
Vector	variables() The list of variables in the model
Vector	variablesWithInitialValue() The list of variales without initial value

Methods inherited from class java.lang.Object

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

Field Detail

sTimeFormat

protected static DecimalFormat sTimeFormat

sDoubleFormat

protected static DecimalFormat sDoubleFormat

sPercentageFormat

protected static DecimalFormat sPercentageFormat

iUnassignedVariables

protected EnumerableCollection iUnassignedVariables

iAssignedVariables

protected EnumerableCollection iAssignedVariables

iPerturbVariables

protected EnumerableCollection iPerturbVariables

Constructor Detail

Model

public Model()

Constructor

Method Detail

variables

public Vector variables()

The list of variables in the model

countVariables

public int countVariables()

The number of variables in the model

addVariable

public void addVariable(Variable variable)

Adds a variable to the model

removeVariable

public void removeVariable(Variable variable)

Removes a variable from the model

constraints

public Vector constraints()

The list of constraints in the model

countConstraints

public int countConstraints()

The number of constraints in the model

addConstraint

public void addConstraint(Constraint constraint)

Adds a constraint to the model

removeConstraint

public void removeConstraint(Constraint constraint)

Removes a constraint from the model

globalConstraints

public Vector globalConstraints()

The list of global constraints in the model

countGlobalConstraints

public int countGlobalConstraints()

The number of global constraints in the model

addGlobalConstraint

public void addGlobalConstraint(GlobalConstraint constraint)

Adds a global constraint to the model

removeGlobalConstraint

public void removeGlobalConstraint(GlobalConstraint constraint)

Removes a global constraint from the model

unassignedVariables

public EnumerableCollection unassignedVariables()

The list of unassigned variables in the model

nrUnassignedVariables

public int nrUnassignedVariables()

Number of unassigned variables

assignedVariables

public EnumerableCollection assignedVariables()

The list of assigned variables in the model

nrAssignedVariables

public int nrAssignedVariables()

Number of assigned variables

perturbVariables

public EnumerableCollection perturbVariables()

The list of perturbation variables in the model, i.e., the variables which has an initial value but which are not assigned with this value.

perturbVariables

public EnumerableCollection perturbVariables(Vector variables)

The list of perturbation variables in the model, i.e., the variables which has an initial value but which are not assigned with this value. Only variables from the given set are considered.

conflictValues

public Set conflictValues(Value value)

Returns the set of confliction variables with this value, if it is assigned to its variable

inConflict

public boolean inConflict(Value value)

Return true if the given value is in conflict with a hard constraint

variablesWithInitialValue

public Vector variablesWithInitialValue()

The list of variales without initial value

invalidateVariablesWithInitialValueCache

protected void invalidateVariablesWithInitialValueCache()

Invalidates cache containing all variables that possess an initial value

beforeAssigned

public void beforeAssigned(long iteration,
                           Value value)

Called before a value is assigned to its variable

beforeUnassigned

public void beforeUnassigned(long iteration,
                             Value value)

Called before a value is unassigned from its variable

afterAssigned

public void afterAssigned(long iteration,
                          Value value)

Called after a value is assigned to its variable

afterUnassigned

public void afterUnassigned(long iteration,
                            Value value)

Called after a value is unassigned from its variable

toString

public String toString()

Overrides:

toString in class Object

getPerc

protected String getPerc(double value,
                         double min,
                         double max)

getPercRev

protected String getPercRev(double value,
                            double min,
                            double max)

getInfo

public Hashtable getInfo()

Returns information about the current solution. Information from all model listeners and constraints is also included.

getExtendedInfo

public Hashtable getExtendedInfo()

Extended information about current solution. Similar to getInfo(), but some more information (that is more expensive to compute) might be added.

getInfo

public Hashtable getInfo(Vector variables)

Returns information about the current solution. Information from all model listeners and constraints is also included. Only variables from the given set are considered.

getBestUnassignedVariables

public int getBestUnassignedVariables()

Returns the number of unassigned variables in the best ever found solution

getBestPerturbations

public int getBestPerturbations()

Returns the number of perturbation variables in the best ever found solution

saveBest

public void saveBest()

Save the current assignment as the best ever found assignment

clearBest

public void clearBest()

Clear the best ever found assignment

restoreBest

public void restoreBest()

Restore the best ever found assignment into the current assignment

bestUnassignedVariables

public EnumerableCollection bestUnassignedVariables()

The list of unassigned variables in the best ever found solution

getTotalValue

public double getTotalValue()

Value of the current solution. It is the sum of all assigned values, i.e., Value.toDouble().

getTotalValue

public double getTotalValue(Vector variables)

Value of the current solution. It is the sum of all assigned values, i.e., Value.toDouble(). Only variables from the given set are considered.

addModelListener

public void addModelListener(ModelListener listener)

Adds a model listener

removeModelListener

public void removeModelListener(ModelListener listener)

Removes a model listener

init

public boolean init(Solver solver)

Model initialization

getModelListeners

public Vector getModelListeners()

The list of model listeners

modelListenerOfType

public ModelListener modelListenerOfType(Class type)

The list of model listeners that are of the given class

conflictConstraints

public Hashtable conflictConstraints(Value value)

The list of constraints which are in a conflict with the given value if it is assigned to its variable. This means the constraints, which adds a value into the set of conflicting values in Constraint.computeConflicts(Value, Set).

unassignedHardConstraints

public Vector unassignedHardConstraints()

The list of hard constraints which contain at least one variable that is not assigned.

getInfoProviders

protected Vector getInfoProviders()

Registered info providers (see InfoProvider)