org.sat4j.specs
Interface ISolver

All Superinterfaces:

IProblem, java.io.Serializable

All Known Implementing Classes:

AbstractSelectorVariablesDecorator, DimacsOutputSolver, GateTranslator, MaxSatDecorator, MinCostDecorator, Minimal4CardinalityModel, Minimal4InclusionModel, MinOneDecorator, ModelIterator, PBSolver, PBSolverClause, PBSolverMerging, PBSolverWithImpliedClause, PseudoOptDecorator, SingleSolutionDetector, SolutionCounter, Solver, SolverDecorator, WeightedMaxSatDecorator

public interface ISolver
extends IProblem, java.io.Serializable

That interface contains all the services available on a SAT solver.

Author:

leberre

Method Summary

void	addAllClauses(IVec<IVecInt> clauses) Create clauses from a set of set of literals.
IConstr	addAtLeast(IVecInt literals, int degree) Create a cardinality constraint of the type "at least n of those literals must be satisfied"
IConstr	addAtMost(IVecInt literals, int degree) Create a cardinality constraint of the type "at most n of those literals must be satisfied"
IConstr	addClause(IVecInt literals) Create a clause from a set of literals The literals are represented by non null integers such that opposite literals a represented by opposite values.
IConstr	addPseudoBoolean(IVecInt lits, IVec<java.math.BigInteger> coeffs, boolean moreThan, java.math.BigInteger d) Create a Pseudo-Boolean constraint of the type "at least n of those literals must be satisfied"
void	clearLearntClauses()
java.util.Map<java.lang.String,java.lang.Number>	getStat() To obtain a map of the available statistics from the solver.
int	getTimeout() Useful to check the internal timeout of the solver.
int	newVar() Deprecated.
int	newVar(int howmany) Create howmany variables in the solver (and thus in the vocabulary).
void	printStat(java.io.PrintStream out, java.lang.String prefix) Deprecated.
void	printStat(java.io.PrintWriter out, java.lang.String prefix) Display statistics to the given output writer
boolean	removeConstr(IConstr c) Remove a constraint returned by one of the add method from the solver.
void	reset() Clean up the internal state of the solver.
void	setExpectedNumberOfClauses(int nb) To inform the solver of the expected number of clauses to read.
void	setTimeout(int t) To set the internal timeout of the solver.
void	setTimeoutMs(long t) To set the internal timeout of the solver.
java.lang.String	toString(java.lang.String prefix) Display a textual representation of the solver configuration.

Methods inherited from interface org.sat4j.specs.IProblem

findModel, findModel, isSatisfiable, isSatisfiable, model, model, nConstraints, nVars

Method Detail

newVar

@Deprecated
int newVar()

Deprecated.

Create a new variable in the solver (and thus in the vocabulary). WE STRONGLY ENCOURAGE TO PRECOMPUTE THE NUMBER OF VARIABLES NEEDED AND TO USE newVar(howmany) INSTEAD. IF YOU EXPERIENCE A PROBLEM OF EFFICIENCY WHEN READING/BUILDING YOUR SAT INSTANCE, PLEASE CHECK THAT YOU ARE NOT USING THAT METHOD.

Returns:

the number of variables available in the vocabulary, which is the identifier of the new variable.

newVar

int newVar(int howmany)

Create howmany variables in the solver (and thus in the vocabulary).

Parameters:

howmany - number of variables to create

Returns:

the total number of variables available in the solver (the highest variable number)

setExpectedNumberOfClauses

void setExpectedNumberOfClauses(int nb)

To inform the solver of the expected number of clauses to read. This is an optional method, that is called when the p cnf line is read in dimacs formatted input file.

Parameters:

nb - the expected number of clauses.

Since:

1.6

addClause

IConstr addClause(IVecInt literals)
                  throws ContradictionException

Create a clause from a set of literals The literals are represented by non null integers such that opposite literals a represented by opposite values. (clasical Dimacs way of representing literals).

Parameters:

literals - a set of literals

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 it contains only falsified literals after unit propagation

See Also:

removeConstr(IConstr)

removeConstr

boolean removeConstr(IConstr c)

Remove a constraint returned by one of the add method from the solver. All learnt clauses will be cleared.

Parameters:

c - a constraint returned by one of the add method.

Returns:

true if the constraint was sucessfully removed.

addAllClauses

void addAllClauses(IVec<IVecInt> clauses)
                   throws ContradictionException

Create clauses from a set of set of literals. This is convenient to create in a single call all the clauses (mandatory for the distributed version of the solver). It is mainly a loop to addClause().

Parameters:

clauses - a vector of set (VecInt) of literals in the dimacs format. The vector can be reused since the solver is not supposed to keep a reference to that vector.

Throws:

ContradictionException - iff the vector of literals is empty or if it contains only falsified literals after unit propagation

See Also:

addClause(IVecInt)

addAtMost

IConstr addAtMost(IVecInt literals,
                  int degree)
                  throws ContradictionException

Create a cardinality constraint of the type "at most n of those literals must be satisfied"

Parameters:

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

degree - 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 it contains more than degree satisfied literals after unit propagation

See Also:

removeConstr(IConstr)

addAtLeast

IConstr addAtLeast(IVecInt literals,
                   int degree)
                   throws ContradictionException

Create a cardinality constraint of the type "at least n of those literals must be satisfied"

Parameters:

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

degree - 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 degree literals are not remaining unfalsified after unit propagation

See Also:

removeConstr(IConstr)

addPseudoBoolean

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

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

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

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:

removeConstr(IConstr)

setTimeout

void setTimeout(int t)

To set the internal timeout of the solver. When the timeout is reached, a timeout exception is launched by the solver.

Parameters:

t - the timeout (in s)

setTimeoutMs

void setTimeoutMs(long t)

To set the internal timeout of the solver. When the timeout is reached, a timeout exception is launched by the solver.

Parameters:

t - the timeout (in milliseconds)

getTimeout

int getTimeout()

Useful to check the internal timeout of the solver.

Returns:

the internal timeout of the solver (in second)

reset

void reset()

Clean up the internal state of the solver.

printStat

@Deprecated
void printStat(java.io.PrintStream out,
                          java.lang.String prefix)

Deprecated.

Display statistics to the given output stream Please use writers instead of stream.

Parameters:

out -

prefix - the prefix to put in front of each line

See Also:

printStat(PrintWriter, String)

printStat

void printStat(java.io.PrintWriter out,
               java.lang.String prefix)

Display statistics to the given output writer

Parameters:

out -

prefix - the prefix to put in front of each line

Since:

1.6

getStat

java.util.Map<java.lang.String,java.lang.Number> getStat()

To obtain a map of the available statistics from the solver. Note that some keys might be specific to some solvers.

Returns:

a Map with the name of the statistics as key.

toString

java.lang.String toString(java.lang.String prefix)

Display a textual representation of the solver configuration.

Parameters:

prefix - the prefix to use on each line.

Returns:

a textual description of the solver internals.

clearLearntClauses

void clearLearntClauses()