org.sat4j.pb

Class LPStringSolver

java.lang.Object

org.sat4j.tools.AbstractOutputSolver

org.sat4j.tools.DimacsStringSolver

org.sat4j.pb.LPStringSolver

All Implemented Interfaces:

Serializable, IPBSolver, IProblem, ISolver, RandomAccessModel

public class LPStringSolver
extends DimacsStringSolver
implements IPBSolver

Solver used to display in a string the pb-instance in OPB format. That solver is useful to produce LP files to be used by third party solvers (of which CPLEX) This is a preliminary implementation

Author:

sroussel

See Also:

Serialized Form

Field Summary

Fields inherited from class org.sat4j.tools.AbstractOutputSolver

firstConstr, fixedNbClauses, nbclauses, nbvars

Constructor Summary

Constructors

Constructor and Description
LPStringSolver()
LPStringSolver(int initSize)

Method Summary

Methods

Modifier and Type	Method and Description
IConstr	addAtLeast(IVecInt literals, int degree)
IConstr	addAtLeast(IVecInt literals, IVec<BigInteger> coeffs, BigInteger degree) Create a pseudo-boolean constraint of the type "at least".
IConstr	addAtLeast(IVecInt literals, IVecInt coeffs, int degree) Create a pseudo-boolean constraint of the type "at least".
IConstr	addAtMost(IVecInt literals, int degree)
IConstr	addAtMost(IVecInt literals, IVec<BigInteger> coeffs, BigInteger degree) Create a pseudo boolean constraint of the type "at most".
IConstr	addAtMost(IVecInt literals, IVecInt coeffs, int degree) Create a pseudo boolean constraint of the type "at most".
IConstr	addClause(IVecInt literals)
IConstr	addExactly(IVecInt literals, IVec<BigInteger> coeffs, BigInteger weight) Create a pseudo-boolean constraint of the type "subset sum".
IConstr	addExactly(IVecInt literals, IVecInt coeffs, int weight) Create a pseudo-boolean constraint of the type "subset sum".
IConstr	addPseudoBoolean(IVecInt lits, IVec<BigInteger> coeffs, boolean moreThan, BigInteger d) Create a Pseudo-Boolean constraint of the type "at least n or at most n of those literals must be satisfied"
String	getExplanation()
ObjectiveFunction	getObjectiveFunction() Retrieve the objective function from the solver.
boolean	isSatisfiable(IVecInt assumps)
boolean	isSatisfiable(IVecInt assumps, boolean global)
int	nConstraints()
int	newVar(int howmany)
void	objectiveFunctionToLP(ObjectiveFunction obj, StringBuffer buffer)
void	setExpectedNumberOfClauses(int nb)
void	setListOfVariablesForExplanation(IVecInt listOfVariables)
void	setObjectiveFunction(ObjectiveFunction obj) Provide an objective function to the solver.
String	toString()
String	toString(String prefix)

Methods inherited from class org.sat4j.tools.DimacsStringSolver

addExactly, getOut, modelWithInternalVariables, newVar, nextFreeVarId, nVars, primeImplicant, printInfos, printStat, realNumberOfVariables, registerLiteral, reset, setNbVars

Methods inherited from class org.sat4j.tools.AbstractOutputSolver

addAllClauses, addBlockingClause, clearLearntClauses, expireTimeout, findModel, findModel, getLogPrefix, getSearchListener, getSolvingEngine, getStat, getTimeout, getTimeoutMs, isDBSimplificationAllowed, isSatisfiable, isSatisfiable, isSolverKeptHot, isVerbose, model, model, primeImplicant, printInfos, printStat, printStat, removeConstr, removeSubsumedConstr, setDBSimplificationAllowed, setKeepSolverHot, setLogPrefix, setSearchListener, setTimeout, setTimeoutMs, setTimeoutOnConflicts, setUnitClauseProvider, setVerbose, unsatExplanation

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.sat4j.specs.ISolver

addAllClauses, addBlockingClause, addExactly, clearLearntClauses, expireTimeout, getLogPrefix, getSearchListener, getSolvingEngine, getStat, getTimeout, getTimeoutMs, isDBSimplificationAllowed, isSolverKeptHot, isVerbose, modelWithInternalVariables, newVar, nextFreeVarId, printStat, printStat, printStat, realNumberOfVariables, registerLiteral, removeConstr, removeSubsumedConstr, reset, setDBSimplificationAllowed, setKeepSolverHot, setLogPrefix, setSearchListener, setTimeout, setTimeoutMs, setTimeoutOnConflicts, setUnitClauseProvider, setVerbose, unsatExplanation

Methods inherited from interface org.sat4j.specs.IProblem

findModel, findModel, isSatisfiable, isSatisfiable, model, nVars, primeImplicant, primeImplicant, printInfos, printInfos

Methods inherited from interface org.sat4j.specs.RandomAccessModel

model

Constructor Detail

LPStringSolver

public LPStringSolver()

LPStringSolver

public LPStringSolver(int initSize)

Parameters:

initSize -

Method Detail

isSatisfiable

public boolean isSatisfiable(IVecInt assumps)
                      throws TimeoutException

Specified by:

isSatisfiable in interface IProblem

Overrides:

isSatisfiable in class AbstractOutputSolver

Throws:

TimeoutException

isSatisfiable

public boolean isSatisfiable(IVecInt assumps,
                    boolean global)
                      throws TimeoutException

Specified by:

isSatisfiable in interface IProblem

Overrides:

isSatisfiable in class AbstractOutputSolver

Throws:

TimeoutException

addPseudoBoolean

public IConstr addPseudoBoolean(IVecInt lits,
                       IVec<BigInteger> coeffs,
                       boolean moreThan,
                       BigInteger d)
                         throws ContradictionException

Description copied from interface: IPBSolver

Create a Pseudo-Boolean constraint of the type "at least n or at most n of those literals must be satisfied"

Specified by:

addPseudoBoolean in interface IPBSolver

Parameters:

lits - a set of literals. The vector can be reused since the solver is not supposed to keep a reference to that vector.

coeffs - the coefficients of the literals. The vector can be reused since the solver is not supposed to keep a reference to that vector.

moreThan - true if it is a constraint >= degree, false if it is a constraint <= degree

d - the degree of the cardinality constraint

Returns:

a reference to the constraint added in the solver, to use in removeConstr().

Throws:

ContradictionException - iff the vector of literals is empty or if the constraint is falsified after unit propagation

See Also:

ISolver.removeConstr(IConstr)

setObjectiveFunction

public void setObjectiveFunction(ObjectiveFunction obj)

Description copied from interface: IPBSolver

Provide an objective function to the solver.

Specified by:

setObjectiveFunction in interface IPBSolver

Parameters:

obj - the objective function

addAtLeast

public IConstr addAtLeast(IVecInt literals,
                 int degree)
                   throws ContradictionException

Specified by:

addAtLeast in interface ISolver

Overrides:

addAtLeast in class DimacsStringSolver

Throws:

ContradictionException

addAtMost

public IConstr addAtMost(IVecInt literals,
                int degree)
                  throws ContradictionException

Specified by:

addAtMost in interface ISolver

Overrides:

addAtMost in class DimacsStringSolver

Throws:

ContradictionException

addClause

public IConstr addClause(IVecInt literals)
                  throws ContradictionException

Specified by:

addClause in interface ISolver

Overrides:

addClause in class DimacsStringSolver

Throws:

ContradictionException

getExplanation

public String getExplanation()

setListOfVariablesForExplanation

public void setListOfVariablesForExplanation(IVecInt listOfVariables)

objectiveFunctionToLP

public void objectiveFunctionToLP(ObjectiveFunction obj,
                         StringBuffer buffer)

toString

public String toString()

Overrides:

toString in class DimacsStringSolver

toString

public String toString(String prefix)

Specified by:

toString in interface ISolver

Overrides:

toString in class DimacsStringSolver

newVar

public int newVar(int howmany)

Specified by:

newVar in interface IProblem

Overrides:

newVar in class DimacsStringSolver

setExpectedNumberOfClauses

public void setExpectedNumberOfClauses(int nb)

Specified by:

setExpectedNumberOfClauses in interface ISolver

Overrides:

setExpectedNumberOfClauses in class DimacsStringSolver

getObjectiveFunction

public ObjectiveFunction getObjectiveFunction()

Description copied from interface: IPBSolver

Retrieve the objective function from the solver.

Specified by:

getObjectiveFunction in interface IPBSolver

Returns:

the objective function

nConstraints

public int nConstraints()

Specified by:

nConstraints in interface IProblem

Overrides:

nConstraints in class DimacsStringSolver

addAtMost

public IConstr addAtMost(IVecInt literals,
                IVecInt coeffs,
                int degree)
                  throws ContradictionException

Description copied from interface: IPBSolver

Create a pseudo boolean constraint of the type "at most".

Specified by:

addAtMost in interface IPBSolver

Parameters:

literals - a set of literals The vector can be reused since the solver is not supposed to keep a reference to that vector.

coeffs - the coefficients of the literals. The vector can be reused since the solver is not supposed to keep a reference to that vector.

degree - the degree of the pseudo-boolean constraint

Returns:

a reference to the constraint added in the solver, to use in removeConstr().

Throws:

ContradictionException - iff the constraint is found trivially unsat.

See Also:

ISolver.removeConstr(IConstr)

addAtMost

public IConstr addAtMost(IVecInt literals,
                IVec<BigInteger> coeffs,
                BigInteger degree)
                  throws ContradictionException

Description copied from interface: IPBSolver

Create a pseudo boolean constraint of the type "at most".

Specified by:

addAtMost in interface IPBSolver

Parameters:

literals - a set of literals The vector can be reused since the solver is not supposed to keep a reference to that vector.

coeffs - the coefficients of the literals. The vector can be reused since the solver is not supposed to keep a reference to that vector.

degree - the degree of the pseudo-boolean constraint

Returns:

a reference to the constraint added in the solver, to use in removeConstr().

Throws:

ContradictionException - iff the constraint is found trivially unsat.

See Also:

ISolver.removeConstr(IConstr)

addAtLeast

public IConstr addAtLeast(IVecInt literals,
                 IVecInt coeffs,
                 int degree)
                   throws ContradictionException

Description copied from interface: IPBSolver

Create a pseudo-boolean constraint of the type "at least".

Specified by:

addAtLeast in interface IPBSolver

Parameters:

literals - a set of literals. The vector can be reused since the solver is not supposed to keep a reference to that vector.

coeffs - the coefficients of the literals. The vector can be reused since the solver is not supposed to keep a reference to that vector.

degree - the degree of the pseudo-boolean constraint

Returns:

a reference to the constraint added in the solver, to use in removeConstr().

Throws:

ContradictionException - iff the constraint is found trivially unsat.

See Also:

ISolver.removeConstr(IConstr)

addAtLeast

public IConstr addAtLeast(IVecInt literals,
                 IVec<BigInteger> coeffs,
                 BigInteger degree)
                   throws ContradictionException

Description copied from interface: IPBSolver

Create a pseudo-boolean constraint of the type "at least".

Specified by:

addAtLeast in interface IPBSolver

Parameters:

literals - a set of literals. The vector can be reused since the solver is not supposed to keep a reference to that vector.

coeffs - the coefficients of the literals. The vector can be reused since the solver is not supposed to keep a reference to that vector.

degree - the degree of the pseudo-boolean constraint

Returns:

a reference to the constraint added in the solver, to use in removeConstr().

Throws:

ContradictionException - iff the constraint is found trivially unsat.

See Also:

ISolver.removeConstr(IConstr)

addExactly

public IConstr addExactly(IVecInt literals,
                 IVecInt coeffs,
                 int weight)
                   throws ContradictionException

Description copied from interface: IPBSolver

Create a pseudo-boolean constraint of the type "subset sum".

Specified by:

addExactly in interface IPBSolver

Parameters:

literals - a set of literals. The vector can be reused since the solver is not supposed to keep a reference to that vector.

coeffs - the coefficients of the literals. The vector can be reused since the solver is not supposed to keep a reference to that vector.

weight - the number of literals that must be satisfied

Returns:

a reference to the constraint added to the solver. It might return an object representing a group of constraints.

Throws:

ContradictionException - iff the constraint is trivially unsatisfiable.

addExactly

public IConstr addExactly(IVecInt literals,
                 IVec<BigInteger> coeffs,
                 BigInteger weight)
                   throws ContradictionException

Description copied from interface: IPBSolver

Create a pseudo-boolean constraint of the type "subset sum".

Specified by:

addExactly in interface IPBSolver

Parameters:

literals - a set of literals. The vector can be reused since the solver is not supposed to keep a reference to that vector.

coeffs - the coefficients of the literals. The vector can be reused since the solver is not supposed to keep a reference to that vector.

weight - the number of literals that must be satisfied

Returns:

a reference to the constraint added to the solver. It might return an object representing a group of constraints.

Throws:

ContradictionException - iff the constraint is trivially unsatisfiable.