net.sf.tweety.logics.fol.reasoner

Class SpassFolReasoner

java.lang.Object

net.sf.tweety.logics.fol.reasoner.FolReasoner

net.sf.tweety.logics.fol.reasoner.SpassFolReasoner

All Implemented Interfaces:

QualitativeReasoner<FolBeliefSet,FolFormula>, Reasoner<java.lang.Boolean,FolBeliefSet,FolFormula>

public class SpassFolReasoner
extends FolReasoner

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.

Author:

Anna Gessler

Field Summary

Fields

Modifier and Type	Field and Description
private Shell	bash Shell to run SPASS.
private java.lang.String	binaryLocation String representation of the SPASS path.
private java.lang.String	cmdOptions Command line options that will be used by SPASS when executing the query.

Fields inherited from class net.sf.tweety.logics.fol.reasoner.FolReasoner

defaultReasoner

Constructor Summary

Constructors

Constructor and Description
SpassFolReasoner(java.lang.String binaryLocation) Constructs a new instance pointing to a specific SPASS
SpassFolReasoner(java.lang.String binaryLocation, Shell bash) Constructs a new instance pointing to a specific SPASS Prover.

Method Summary

Modifier and Type	Method and Description
boolean	equivalent(FolBeliefSet kb, FolFormula a, FolFormula b) This method determines whether two formulas are equivalent wrt.
private boolean	evaluateResult(java.lang.String output) Evaluates SPASS results.
java.lang.Boolean	query(FolBeliefSet kb, FolFormula query) Queries the given belief base for the given formula.
java.lang.String	queryProof(FolBeliefSet kb, Formula query) Determines the answer wrt.
void	setCmdOptions(java.lang.String s) Sets the command line options that will be used by SPASS when executing the query.

Methods inherited from class net.sf.tweety.logics.fol.reasoner.FolReasoner

getDefaultReasoner, setDefaultReasoner

Methods inherited from class java.lang.Object

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

Field Detail

binaryLocation

private java.lang.String binaryLocation

String representation of the SPASS path.

bash

private Shell bash

Shell to run SPASS.

cmdOptions

private java.lang.String cmdOptions

Command line options that will be used by SPASS when executing the query. The default value disables most outputs except for the result and enables TPTP input format instead of SPASS input format.

Constructor Detail

SpassFolReasoner

public SpassFolReasoner(java.lang.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

SpassFolReasoner

public SpassFolReasoner(java.lang.String binaryLocation)

Constructs a new instance pointing to a specific SPASS

Parameters:

binaryLocation - of the SPASS executable on the hard drive

Method Detail

setCmdOptions

public void setCmdOptions(java.lang.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 java.lang.Boolean query(FolBeliefSet kb,
                               FolFormula query)

Description copied from interface: Reasoner

Queries the given belief base for the given formula.

Specified by:

query in interface QualitativeReasoner<FolBeliefSet,FolFormula>

Specified by:

query in interface Reasoner<java.lang.Boolean,FolBeliefSet,FolFormula>

Specified by:

query in class FolReasoner

Parameters:

kb - a belief base

query - a formula

Returns:

the answer to the query

queryProof

public java.lang.String queryProof(FolBeliefSet kb,
                                   Formula query)

Determines the answer wrt. to the given query and returns the proof (if applicable). May decrease SPASS's performance, use net.sf.tweety.logics.SpassFolReasoner.reasoner.SPASS#query(Formula) if only a yes/no result is needed.

Parameters:

query - a formula

Returns:

a string containing proof documentation

evaluateResult

private boolean evaluateResult(java.lang.String output)

Evaluates SPASS results.

Parameters:

output - of a SPASS query

Returns:

true if a proof was found, false otherwise

equivalent

public boolean equivalent(FolBeliefSet kb,
                          FolFormula a,
                          FolFormula b)

Description copied from class: FolReasoner

This method determines whether two formulas are equivalent wrt. to the given knowledge base.

Specified by:

equivalent in class FolReasoner

Parameters:

kb - the knowledge base

a - the first formula.

b - the second formula.

Returns:

the answer to the query.