Package org.tweetyproject.lp.asp.syntax

Class AggregateAtom

java.lang.Object

org.tweetyproject.lp.asp.syntax.ASPElement

org.tweetyproject.lp.asp.syntax.ASPBodyElement

org.tweetyproject.lp.asp.syntax.AggregateAtom

All Implemented Interfaces:

Formula, ComplexLogicalFormula, LogicStructure, SimpleLogicalFormula

public class AggregateAtom
extends ASPBodyElement

This class represents an aggregate. Aggregates are functions that range over sets of terms and literals and evaluate to some value. For example, using the aggregate function #count one can easily express "the number of employees of a department has to be greater than 0".
An aggregate function together with the terms and literals it ranges over and a comparison (like >= 0) is called an aggregate atom and can appear in the body of a rule.
If you want to use an aggregate atom as the head of a rule (as is allowed in some standards like clingo), use AggregateHead

Author:

Tim Janus, Thomas Vengels, Anna Gessler

Constructor Summary

Constructors

Constructor	Description
AggregateAtom()	Empty default constructor.
AggregateAtom(List<ASPBodyElement> literals, int leftBound, int rightBound)	Creates a new cardinality rule, meaning an aggregate of the form "leftBound <= #count { elements } <= rightBound" with the given literals and the given integer bounds.
AggregateAtom(AggregateAtom other)	Copy-Constructor
AggregateAtom(ASPOperator.AggregateFunction function, List<AggregateElement> elements)	Creates a new Aggregate with the given aggregate function and the given aggregate elements.
AggregateAtom(ASPOperator.AggregateFunction function, List<AggregateElement> elements, ASPOperator.BinaryOperator rightRelation, int rightBound)	Creates a new Aggregate of the form "#func { elements } op rightBound" with the given aggregate function #func, the given aggregate elements, the given aggregate relation op and the given rightBound.
AggregateAtom(ASPOperator.AggregateFunction function, List<AggregateElement> elements, ASPOperator.BinaryOperator leftRelation, int leftBound, ASPOperator.BinaryOperator rightRelation, int rightBound)	Creates a new Aggregate of the form "leftBound op #func { elements } op rightBound" with the given aggregate function, the given aggregate elements, and the given left and right aggregate relations and integer bounds.
AggregateAtom(ASPOperator.AggregateFunction function, List<AggregateElement> elements, ASPOperator.BinaryOperator rightRelation, Term<?> rightBound)	Creates a new Aggregate of the form "#func { elements } op rightBound" with the given aggregate function #func, the given aggregate elements, the given aggregate relation op and the given rightBound.
AggregateAtom(ASPOperator.AggregateFunction function, List<AggregateElement> elements, ASPOperator.BinaryOperator leftRelation, Term<?> leftBound, ASPOperator.BinaryOperator rightRelation, Term<?> rightBound)	Creates a new Aggregate of the form "leftBound leftOp #func { elements } rightOp rightBound" with the given aggregate function, the given aggregate elements, and the given left and right aggregate relations and bounds.

Method Summary

Modifier and Type	Method	Description
AggregateAtom	clone()	Creates a deep copy of this formula
boolean	equals(Object obj)
List<AggregateElement>	getAggregateElements()	Return the elements that the aggregate ranges over.
Set<ASPAtom>	getAtoms()	Processes the set of all atoms which appear in this formula
ASPOperator.AggregateFunction	getFunction()	Return the aggregate function
Term<?>	getLeftGuard()	Get the left relation term (left guard).
ASPOperator.BinaryOperator	getLeftOperator()	Returns the operator of the left aggregate relation.
SortedSet<ASPLiteral>	getLiterals()	Returns all literals in this element in form of a SortedSet.
Set<Predicate>	getPredicates()	Processes the set of all predicates which appear in this formula
Term<?>	getRightGuard()	Return the right relation term (right guard).
ASPOperator.BinaryOperator	getRightOperator()	Returns the operator of the right aggregate relation.
FolSignature	getSignature()	Returns the signature of the language of this formula.
Set<Term<?>>	getTerms()
<C extends Term<?>> Set<C>	getTerms(Class<C> cls)	Processes the set containing all terms of type C.
int	hashCode()
boolean	hasLeftRelation()	Returns true if the aggregate has a left aggregate relation (meaning a term that the aggregate's resulting value will be compared to using a comparative operator).
boolean	hasRightRelation()	Returns true if the aggregate has a right aggregate relation (meaning a term that the aggregate's resulting value will be compared to using a comparative operator).
boolean	isLiteral()
String	printToClingo()	Returns a representation of this ASP element in clingo (potassco) syntax.
String	printToDLV()	Returns a representation of this ASP element in DLV syntax.
void	setAggregateElements(List<AggregateElement> aggregateElements)	Set the elements that the aggregate ranges over.
void	setFunction(ASPOperator.AggregateFunction function)	Sets the aggregate function.
void	setLeft(int term, ASPOperator.BinaryOperator op)	Set the left relation term and operator.
void	setLeft(Term<?> term, ASPOperator.BinaryOperator op)	Set the left relation term and operator.
void	setLeftGuard(int relationTerm)	Set the left relation term (left guard).
void	setLeftGuard(Term<?> relationTerm)	Set the left relation term (left guard).
void	setLeftOperator(ASPOperator.BinaryOperator op)	Sets the operator of the left aggregate relation.
void	setRight(int term, ASPOperator.BinaryOperator op)	Set the right relation term and operator.
void	setRight(Term<?> term, ASPOperator.BinaryOperator op)	Set the right relation term and operator.
void	setRightGuard(int relationTerm)	Set the right relation term (right guard).
void	setRightGuard(Term<?> relationTerm)	Set the right relation term (right guard).
void	setRightOperator(ASPOperator.BinaryOperator op)	Sets the operator of the right aggregate relation.
AggregateAtom	substitute(Term<?> t, Term<?> v)	Substitutes all occurrences of term "v" in this formula by term "t" and returns the new formula.
String	toString()

Methods inherited from class org.tweetyproject.lp.asp.syntax.ASPElement

containsTermsOfType, exchange, getPredicateCls, isGround, isWellFormed, substitute

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Constructor Details

AggregateAtom

public AggregateAtom()

Empty default constructor.

AggregateAtom

public AggregateAtom(ASPOperator.AggregateFunction function,
 List<AggregateElement> elements)

Creates a new Aggregate with the given aggregate function and the given aggregate elements.

Parameters:

function - an aggregate function

elements - list of aggregate elements

AggregateAtom

public AggregateAtom(ASPOperator.AggregateFunction function,
 List<AggregateElement> elements,
 ASPOperator.BinaryOperator rightRelation,
 Term<?> rightBound)

Creates a new Aggregate of the form "#func { elements } op rightBound" with the given aggregate function #func, the given aggregate elements, the given aggregate relation op and the given rightBound.

Parameters:

function - an aggregate function

elements - list of aggregate elements

rightRelation - the relation

rightBound - some term

AggregateAtom

public AggregateAtom(ASPOperator.AggregateFunction function,
 List<AggregateElement> elements,
 ASPOperator.BinaryOperator rightRelation,
 int rightBound)

Creates a new Aggregate of the form "#func { elements } op rightBound" with the given aggregate function #func, the given aggregate elements, the given aggregate relation op and the given rightBound.

Parameters:

function - an aggregate function

elements - list of aggregate elements

rightRelation - the relation

rightBound - integer

AggregateAtom

public AggregateAtom(ASPOperator.AggregateFunction function,
 List<AggregateElement> elements,
 ASPOperator.BinaryOperator leftRelation,
 Term<?> leftBound,
 ASPOperator.BinaryOperator rightRelation,
 Term<?> rightBound)

Creates a new Aggregate of the form "leftBound leftOp #func { elements } rightOp rightBound" with the given aggregate function, the given aggregate elements, and the given left and right aggregate relations and bounds.

Parameters:

function - an aggregate function

elements - list of aggregate elements

leftRelation - relation

leftBound - term

rightRelation - relation

rightBound - term

AggregateAtom

public AggregateAtom(ASPOperator.AggregateFunction function,
 List<AggregateElement> elements,
 ASPOperator.BinaryOperator leftRelation,
 int leftBound,
 ASPOperator.BinaryOperator rightRelation,
 int rightBound)

Creates a new Aggregate of the form "leftBound op #func { elements } op rightBound" with the given aggregate function, the given aggregate elements, and the given left and right aggregate relations and integer bounds.

Parameters:

function - an aggregate function

elements - list of aggregate elements

leftRelation - relation

leftBound - integer

rightRelation - relation

rightBound - integer

AggregateAtom

public AggregateAtom(List<ASPBodyElement> literals,
 int leftBound,
 int rightBound)

Creates a new cardinality rule, meaning an aggregate of the form "leftBound <= #count { elements } <= rightBound" with the given literals and the given integer bounds.

Parameters:

literals - of the cardinality rule

leftBound - of the cardinality rule

rightBound - of the cardinality rule

AggregateAtom

public AggregateAtom(AggregateAtom other)

Copy-Constructor

Parameters:

other - another AggregateAtom

Method Details

getLiterals

public SortedSet<ASPLiteral> getLiterals()

Description copied from class: ASPBodyElement

Returns all literals in this element in form of a SortedSet. Literals are atoms or strict negations of atoms.

Specified by:

getLiterals in class ASPBodyElement

Returns:

all the literals used in the rule element

getPredicates

public Set<Predicate> getPredicates()

Description copied from interface: SimpleLogicalFormula

Processes the set of all predicates which appear in this formula

Specified by:

getPredicates in interface SimpleLogicalFormula

Specified by:

getPredicates in class ASPElement

Returns:

all predicates that appear in this formula

getAtoms

public Set<ASPAtom> getAtoms()

Description copied from interface: SimpleLogicalFormula

Processes the set of all atoms which appear in this formula

Specified by:

getAtoms in interface SimpleLogicalFormula

Specified by:

getAtoms in class ASPElement

Returns:

The set of all atoms

substitute

public AggregateAtom substitute(Term<?> t,
 Term<?> v)

Description copied from interface: ComplexLogicalFormula

Substitutes all occurrences of term "v" in this formula by term "t" and returns the new formula.

Specified by:

substitute in interface ComplexLogicalFormula

Specified by:

substitute in class ASPBodyElement

Parameters:

t - the term to be substituted.

v - the term to substitute.

Returns:

a formula where every occurrence of "v" is replaced by "t".

getSignature

public FolSignature getSignature()

Description copied from interface: Formula

Returns the signature of the language of this formula.

Specified by:

getSignature in interface Formula

Specified by:

getSignature in class ASPElement

Returns:

the signature of the language of this formula.

clone

public AggregateAtom clone()

Description copied from interface: SimpleLogicalFormula

Creates a deep copy of this formula

Specified by:

clone in interface ComplexLogicalFormula

Specified by:

clone in interface SimpleLogicalFormula

Specified by:

clone in class ASPElement

Returns:

the cloned formula

isLiteral

public boolean isLiteral()

Returns:

true if the formula represents a literal in the language or false otherwise

getTerms

public Set<Term<?>> getTerms()

Returns:

a set containing all terms of this logical structure

getTerms

public <C extends Term<?>> Set<C> getTerms(Class<C> cls)

Description copied from interface: LogicStructure

Processes the set containing all terms of type C. This method uses the equals method of the given Class and therefore does not add terms which are sub classes of type C to the set.

Type Parameters:

C - the type of terms

Parameters:

cls - The Class structure containing type information about the searched term

Returns:

A set containing all terms of type C of this logical structure

getAggregateElements

public List<AggregateElement> getAggregateElements()

Return the elements that the aggregate ranges over.

Returns:

the elements that the aggregate ranges over.

setAggregateElements

public void setAggregateElements(List<AggregateElement> aggregateElements)

Set the elements that the aggregate ranges over.

Parameters:

aggregateElements - the elements

hasLeftRelation

public boolean hasLeftRelation()

Returns true if the aggregate has a left aggregate relation (meaning a term that the aggregate's resulting value will be compared to using a comparative operator).

Returns:

true if aggregate has left aggregate relation

hasRightRelation

public boolean hasRightRelation()

Returns true if the aggregate has a right aggregate relation (meaning a term that the aggregate's resulting value will be compared to using a comparative operator).

Returns:

true if aggregate has right aggregate relation

getFunction

public ASPOperator.AggregateFunction getFunction()

Return the aggregate function

Returns:

the aggregate function

setFunction

public void setFunction(ASPOperator.AggregateFunction function)

Sets the aggregate function.

Parameters:

function - an aggregate function

getRightOperator

public ASPOperator.BinaryOperator getRightOperator()

Returns the operator of the right aggregate relation.

Returns:

comparative operator

setRightOperator

public void setRightOperator(ASPOperator.BinaryOperator op)

Sets the operator of the right aggregate relation.

Parameters:

op - comparative operator

getRightGuard

public Term<?> getRightGuard()

Return the right relation term (right guard).

Returns:

the right relation term (right guard).

setRightGuard

public void setRightGuard(Term<?> relationTerm)

Set the right relation term (right guard).

Parameters:

relationTerm - some term

setRightGuard

public void setRightGuard(int relationTerm)

Set the right relation term (right guard).

Parameters:

relationTerm - some integer

setRight

public void setRight(Term<?> term,
 ASPOperator.BinaryOperator op)

Set the right relation term and operator.

Parameters:

term - the term

op - the op

setRight

public void setRight(int term,
 ASPOperator.BinaryOperator op)

Set the right relation term and operator.

Parameters:

term - , an integer

op - the op

getLeftOperator

public ASPOperator.BinaryOperator getLeftOperator()

Returns the operator of the left aggregate relation.

Returns:

comparative operator

setLeftOperator

public void setLeftOperator(ASPOperator.BinaryOperator op)

Sets the operator of the left aggregate relation.

Parameters:

op - comparative operator

getLeftGuard

public Term<?> getLeftGuard()

Get the left relation term (left guard).

Returns:

Term

setLeftGuard

public void setLeftGuard(Term<?> relationTerm)

Set the left relation term (left guard).

Parameters:

relationTerm - some term

setLeftGuard

public void setLeftGuard(int relationTerm)

Set the left relation term (left guard).

Parameters:

relationTerm - some integer

setLeft

public void setLeft(Term<?> term,
 ASPOperator.BinaryOperator op)

Set the left relation term and operator.

Parameters:

term - the term

op - the op

setLeft

public void setLeft(int term,
 ASPOperator.BinaryOperator op)

Set the left relation term and operator.

Parameters:

term - , an integer

op - the op

toString

public String toString()

Overrides:

toString in class Object

printToClingo

public String printToClingo()

Description copied from class: ASPElement

Returns a representation of this ASP element in clingo (potassco) syntax. See https://potassco.org/ for more information.

Overrides:

printToClingo in class ASPElement

Returns:

String representation in clingo syntax

printToDLV

public String printToDLV()

Description copied from class: ASPElement

Returns a representation of this ASP element in DLV syntax. See http://www.dlvsystem.com/html/DLV_User_Manual.html for more information.

Overrides:

printToDLV in class ASPElement

Returns:

String representation in DLV syntax

hashCode

public int hashCode()

Specified by:

hashCode in interface SimpleLogicalFormula

Overrides:

hashCode in class Object

equals

public boolean equals(Object obj)

Specified by:

equals in interface SimpleLogicalFormula

Overrides:

equals in class Object