Package org.tweetyproject.logics.ml.reasoner

Class SPASSMlReasoner

java.lang.Object

org.tweetyproject.logics.ml.reasoner.AbstractMlReasoner

org.tweetyproject.logics.ml.reasoner.SPASSMlReasoner

All Implemented Interfaces:

QualitativeReasoner<MlBeliefSet,FolFormula>, Reasoner<Boolean,MlBeliefSet,FolFormula>

public class SPASSMlReasoner
extends AbstractMlReasoner

Invokes SPASS (http://www.mpi-inf.mpg.de/departments/automation-of-logic/software/spass-workbench/), an automated theorem prover for first-order logic, modal logic and description logics.
Note: There are unresolved errors for some cases, see org.tweetyproject.logics.ml.SPASSTest#ComplexQueryTest() for examples.

Author:

Anna Gessler, Matthias Thimm

Field Summary

Fields inherited from class org.tweetyproject.logics.ml.reasoner.AbstractMlReasoner

defaultReasoner

Constructor Summary

Constructors

Constructor	Description
SPASSMlReasoner(String binaryLocation)	Constructs a new instance pointing to a specific SPASS
SPASSMlReasoner(String binaryLocation, Shell bash)	Constructs a new instance pointing to a specific SPASS Prover.

Method Summary

Modifier and Type	Method	Description
boolean	isInstalled()	Checks whether the underlying solver or reasoning mechanism used by this reasoner is installed and available for use.
Boolean	query(MlBeliefSet kb, FolFormula query)	Queries the given belief base with the provided formula and returns a boolean result.
String	queryProof(MlBeliefSet kb, Formula query)	Determines the answer wrt.
void	setCmdOptions(String s)	Sets the command line options that will be used by SPASS when executing the query.

Methods inherited from class org.tweetyproject.logics.ml.reasoner.AbstractMlReasoner

getDefaultReasoner, setDefaultReasoner

Methods inherited from class java.lang.Object

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

Constructor Details

SPASSMlReasoner

public SPASSMlReasoner(String binaryLocation,
 Shell bash)

Constructs a new instance pointing to a specific SPASS Prover.

Parameters:

binaryLocation - of the SPASS executable on the hard drive

bash - shell to run commands

SPASSMlReasoner

public SPASSMlReasoner(String binaryLocation)

Constructs a new instance pointing to a specific SPASS

Parameters:

binaryLocation - of the SPASS executable on the hard drive

Method Details

setCmdOptions

public void setCmdOptions(String s)

Sets the command line options that will be used by SPASS when executing the query.

Parameters:

s - a string containing the command line arguments

query

public Boolean query(MlBeliefSet kb,
 FolFormula query)

Description copied from interface: QualitativeReasoner

Queries the given belief base with the provided formula and returns a boolean result. The result indicates whether the formula is entailed or satisfied by the belief base according to the qualitative reasoning method implemented by the reasoner.

Specified by:

query in interface QualitativeReasoner<MlBeliefSet,FolFormula>

Specified by:

query in interface Reasoner<Boolean,MlBeliefSet,FolFormula>

Specified by:

query in class AbstractMlReasoner

Parameters:

kb - The belief base to be queried.

query - The formula for which the query is made.

Returns:

`TRUE` if the formula is entailed or satisfied by the belief base, `FALSE` otherwise.

queryProof

public String queryProof(MlBeliefSet kb,
 Formula query)

Determines the answer wrt. to the given query and returns the proof (if applicable). May decrease SPASS's performance, use query(MlBeliefSet,FolFormula) if only a yes/no result is needed.

Parameters:

kb - a modal belief set

query - a formula

Returns:

a string containing proof documentation

isInstalled

public boolean isInstalled()

Description copied from interface: QualitativeReasoner

Checks whether the underlying solver or reasoning mechanism used by this reasoner is installed and available for use. This can be helpful when the reasoner depends on external tools or libraries for performing the reasoning tasks.

Returns:

`true` if the solver is installed and available, `false` otherwise.