Class DungTheory

java.lang.Object

org.tweetyproject.commons.BeliefSet<Argument, DungSignature>

org.tweetyproject.arg.dung.syntax.DungTheory

All Implemented Interfaces:

Comparable<DungTheory>, Iterable<Argument>, Collection<Argument>, ArgumentationFramework<Argument>, BeliefBase, GeneralGraph<Argument>, Graph<Argument>

Direct Known Subclasses:

ClaimBasedTheory, ConstrainedArgumentationFramework, EpistemicArgumentationFramework, ExecutableDungTheory, IncompleteTheory, InducedTheory, ProbabilisticArgumentationFramework, SocialAbstractArgumentationFramework, StructuredArgumentationFramework, WeightedArgumentationFramework, WeightedDungTheory

public class DungTheory
extends BeliefSet<Argument, DungSignature>
implements Graph<Argument>, Comparable<DungTheory>, ArgumentationFramework<Argument>

This class implements an abstract argumentation theory in the sense of Dung.

See

Phan Minh Dung. On the Acceptability of Arguments and its Fundamental Role in Nonmonotonic Reasoning, Logic Programming and n-Person Games. In Artificial Intelligence, Volume 77(2):321-358. 1995

Author:

Matthias Thimm, Tjitze Rienstra

Field Summary

Fields inherited from class org.tweetyproject.commons.BeliefSet

EQUALS_USES_SIGNATURE

Fields inherited from interface org.tweetyproject.graphs.Graph

IGNORE_SELFLOOPS, INVERT_SELFLOOPS, REMOVE_SELFLOOPS

Constructor Summary

Constructors

Constructor	Description
DungTheory()	Default constructor; initializes empty sets of arguments and attacks
DungTheory(Graph<Argument> graph)	Creates a new theory from the given graph.

Method Summary

Modifier and Type	Method	Description
boolean	add(Argument argument)	Adds the given node to this graph.
boolean	add(Attack attack)	Adds the given attack to this dung theory.
boolean	add(Attack... attacks)	Adds the given attacks to this dung theory.
boolean	add(DungTheory theory)	Adds all arguments and attacks of the given theory to this theory
boolean	add(GeneralEdge<Argument> edge)	Adds the given edge to this graph.
boolean	addAllAttacks(Collection<? extends Attack> c)	Adds the set of attacks to this Dung theory.
boolean	addAttack(Argument attacker, Argument attacked)	Adds an attack from the first argument to the second to thisDdung theory.
boolean	areAdjacent(Argument a, Argument b)	Returns "true" iff the two nodes are connected by a directed edge from a to b or an undirected edge.
DungTheory	clone()
int	compareTo(DungTheory o)
boolean	contains(Object o)	Returns "true" when this graph contains the given node or edge.
boolean	containsAll(Collection<?> c)	Checks if the argumentation framework contains all the elements in the given collection.
boolean	containsAttack(Attack att)	Checks whether this theory contains the given attack.
<S extends Node> boolean	containsCycle()	Checks whether there is at least one cycle in this DungTheory.
<S extends Node> boolean	containsOddCycle()	Checks whether there is at least on eodd cycle in this DungTheory.
boolean	equals(Object obj)
boolean	equalsIn(HashSet<DungTheory> setOfEquals)	Method to check if an equal object to this object is contained in the specified set
boolean	existsDirectedPath(Argument node1, Argument node2)	Checks whether there is a (directed) path from node1 to node2.
Extension<DungTheory>	faf(Extension<DungTheory> extension)	The characteristic function of an abstract argumentation framework: F_AF(S) = {A|A is acceptable wrt.
Matrix	getAdjacencyMatrix()	Returns the adjacency matrix of this graph (the order of the nodes is the same as returned by "iterator()").
Collection<Argument>	getAttacked(Collection<Argument> args)	Computes the set {A | (arg,A) in attacks for some arg in args}.
Set<Argument>	getAttacked(Argument argument)	Computes the set {A | (argument,A) in attacks}.
Collection<Argument>	getAttackers(Collection<Argument> args)	Computes the set {A | (A,arg) in attacks for some arg in args}.
Set<Argument>	getAttackers(Argument argument)	Computes the set {A | (A,argument) in attacks}.
Set<Attack>	getAttacks()	Returns all attacks of this theory.
Set<Attack>	getBidirectionalAttacks()	Returns all bidirectional attacks of this theory.
Collection<Argument>	getChildren(Node node)	Returns the set of children (node connected via an undirected edge or a directed edge where the given node is the parent) of the given node.
DungTheory	getComplementGraph(int selfloops)	Returns the complement graph of this graph, i.e.
Collection<Graph<Argument>>	getComponents()
Collection<Collection<Argument>>	getConnectedComponents()	Returns the set of (simple) connected components of this graph.
Edge<Argument>	getEdge(Argument a, Argument b)	Returns the corresponding edge (a,b) if a and b are adjacent.
Collection<? extends Edge<? extends Argument>>	getEdges()	Returns the edges of this graph.
Collection<Graph<Argument>>	getInducedSubgraphs()
Signature	getMinimalSignature()	Returns the signature of the language of this knowledge base.
Collection<Argument>	getNeighbors(Argument node)	Returns the set of neighbors of the given node.
Collection<Argument>	getNodes()	Returns the nodes of this graph.
int	getNumberOfEdges()	Returns the number of edges in this graph.
int	getNumberOfNodes()	Returns the number of nodes in this graph.
Collection<Argument>	getParents(Node node)	Returns the set of parents (node connected via an undirected edge or a directed edge where the given node is the child) of the given node.
DungTheory	getReduct(Collection<Argument> arguments)	computes the reduct of bbase wrt.
DungTheory	getReduct(Argument arg)	computes the reduct of this wrt.
Graph<Argument>	getRestriction(Collection<Argument> arguments)	Returns a copy of this graph that contains only the specified nodes and all corresponding edges between them.
Collection<Collection<Argument>>	getStronglyConnectedComponents()	Returns the strongly connected components of this graph.
Collection<Graph<Argument>>	getSubgraphs()	Returns the set of sub graphs of this graph.
Collection<Argument>	getUnattackedAttackers(Collection<Argument> ext)	Returns the set of arguments b such that a is in ext and there is no c in ext such that (c,b) is an attack.
Collection<Attack>	getUndefendedAttacks(Collection<Argument> ext)	Returns the set of attacks (b,a) such that a is in ext and there is no c in ext such that (c,b) is an attack.
boolean	hasAttackBranch(Argument a)	If this graph is acyclic, this method checks if the given argument has an attack branch, i.e.
boolean	hasDefenseBranch(Argument a)	If this graph is acyclic, this method checks if the given argument has a defense branch, i.e.
int	hashCode()
boolean	hasSelfLoops()	Returns "true" iff the graph has a self loop (an edge from a node to itself).
boolean	isAcceptable(Argument argument, Extension<DungTheory> ext)	returns true if every attacker on argument is attacked by some accepted argument wrt.
boolean	isAdmissible(Extension<DungTheory> ext)	returns true if every accepted argument of this is defended by some accepted argument wrt.
boolean	isAttackBranch(Argument a, Argument b)	Checks whether the path from b to a is an attack branch, i.e.
boolean	isAttacked(Extension<DungTheory> ext1, Extension<DungTheory> ext2)	returns true if some argument of ext2 attacks some argument in ext1
boolean	isAttacked(Argument argument, Extension<? extends ArgumentationFramework<?>> ext)	returns true if some argument of ext attacks argument.
boolean	isAttackedBy(Argument argument, Collection<Argument> ext)	returns true if some argument of ext is attacked by argument.
boolean	isAttackedBy(Argument arg1, Argument arg2)	Checks whether arg1 is attacked by arg2.
boolean	isAttackingAllOtherArguments(Extension<? extends ArgumentationFramework<Argument>> ext)	returns true if arguments attack all other arguments in the theory
boolean	isCoherent()	Determines if the theory is coherent, i.e., if each preferred extension is stable
boolean	isComplete(Extension<DungTheory> e)	Checks whether the given extension is complete wrt.
boolean	isConflictFree(Collection<Argument> ext)	returns true if no accepted argument attacks another one in the set
boolean	isConflictFree(Extension<DungTheory> ext)	returns true if no accepted argument attacks another accepted one in this interpretation wrt.
boolean	isDefenseBranch(Argument a, Argument b)	Checks whether the path from b to a is a defense branch, i.e.
boolean	isIndirectAttack(Argument arg1, Argument arg2)	Checks whether "arg1" indirectly attacks "arg2", i.e.
boolean	isPreferred(Extension<DungTheory> e)	Checks whether the given extension is preferred wrt.
boolean	isRelativelyCoherent()	Determines if the theory is relatively coherent, i.e., if the grounded extension coincides with the intersection of all preferred extensions
boolean	isStable(Extension<DungTheory> e)	Checks whether the given extension is stable wrt.
boolean	isStronglyDefendedBy(Argument arg, Collection<Argument> ext)	Checks whether a specified argument is strongly defended by the given set of arguments.
boolean	isSupport(Argument arg1, Argument arg2)	Checks whether "arg1" supports "arg2", i.e.
boolean	isWeightedGraph()	Checks whether this graph only contains weighted edges.
boolean	isWellFounded()	returns true iff the theory is well-founded, i.e., there is no infinite sequence A1,A2,...
String	prettyPrint()	Pretty print of the theory.
boolean	remove(Argument a)	Removes the argument and all its attacks
boolean	remove(Attack attack)	Removes the given attack from this Dung theory.
boolean	removeAll(Collection<?> c)
String	toString()

Methods inherited from class org.tweetyproject.commons.BeliefSet

add, addAll, clear, getSignature, isEmpty, iterator, remove, retainAll, setSignature, size, toArray, toArray, toString

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.util.Collection

parallelStream, removeIf, spliterator, stream, toArray

Methods inherited from interface org.tweetyproject.graphs.Graph

iterator

Methods inherited from interface java.lang.Iterable

forEach

Constructor Details

DungTheory

public DungTheory()

Default constructor; initializes empty sets of arguments and attacks

DungTheory

public DungTheory(Graph<Argument> graph)

Creates a new theory from the given graph.

Parameters:

graph - some graph

Method Details

clone

public DungTheory clone()

getMinimalSignature

public Signature getMinimalSignature()

Description copied from interface: BeliefBase

Returns the signature of the language of this knowledge base.

Specified by:

getMinimalSignature in interface BeliefBase

Returns:

the signature of the language of this knowledge base.

isAttackingAllOtherArguments

public boolean isAttackingAllOtherArguments(Extension<? extends ArgumentationFramework<Argument>> ext)

returns true if arguments attack all other arguments in the theory

Parameters:

ext - An extension contains a set of arguments.

Returns:

true if arguments attack all other arguments in the theory

isWellFounded

public boolean isWellFounded()

returns true iff the theory is well-founded, i.e., there is no infinite sequence A1,A2,... of arguments with Ai attacking Ai+1

Returns:

true iff the theory is well-founded

isAcceptable

public boolean isAcceptable(Argument argument,
 Extension<DungTheory> ext)

returns true if every attacker on argument is attacked by some accepted argument wrt. the given theory.

Parameters:

argument - an argument

ext - an extension (the knowledge base)

Returns:

true if every attacker on argument is attacked by some accepted argument wrt. the given theory.

isConflictFree

public boolean isConflictFree(Extension<DungTheory> ext)

returns true if no accepted argument attacks another accepted one in this interpretation wrt. the given theory.

Parameters:

ext - an extension

Returns:

true if no accepted argument attacks another accepted one in this interpretation wrt. the given theory.

isConflictFree

public boolean isConflictFree(Collection<Argument> ext)

returns true if no accepted argument attacks another one in the set

Parameters:

ext - a set of arguments

Returns:

true if no accepted argument attacks another one in the set

isAdmissible

public boolean isAdmissible(Extension<DungTheory> ext)

returns true if every accepted argument of this is defended by some accepted argument wrt. the given Dung theory.

Parameters:

ext - an extension

Returns:

true, if every accepted argument of this is defended by some accepted argument wrt. the given Dung theory.

isStronglyDefendedBy

public boolean isStronglyDefendedBy(Argument arg,
 Collection<Argument> ext)

Checks whether a specified argument is strongly defended by the given set of arguments.

Parameters:

arg - some argument

ext - a set of arguments

Returns:

true, iff the specified argument is strongly defended by the set

isCoherent

public boolean isCoherent()

Determines if the theory is coherent, i.e., if each preferred extension is stable

Returns:

true if the theory is coherent

isRelativelyCoherent

public boolean isRelativelyCoherent()

Determines if the theory is relatively coherent, i.e., if the grounded extension coincides with the intersection of all preferred extensions

Returns:

true if the theory is relatively coherent

getAttackers

public Set<Argument> getAttackers(Argument argument)

Computes the set {A | (A,argument) in attacks}.

Parameters:

argument - an argument

Returns:

the set of all arguments that attack argument.

getAttackers

public Collection<Argument> getAttackers(Collection<Argument> args)

Computes the set {A | (A,arg) in attacks for some arg in args}.

Parameters:

args - a set of arguments

Returns:

the set of all arguments that attack some argument in args.

getAttacked

public Set<Argument> getAttacked(Argument argument)

Computes the set {A | (argument,A) in attacks}.

Parameters:

argument - an argument

Returns:

the set of all arguments that are attacked by argument.

getAttacked

public Collection<Argument> getAttacked(Collection<Argument> args)

Computes the set {A | (arg,A) in attacks for some arg in args}.

Parameters:

args - a set of arguments

Returns:

the set of all arguments that are attacked by some argument in args.

isAttacked

public boolean isAttacked(Argument argument,
 Extension<? extends ArgumentationFramework<?>> ext)

returns true if some argument of ext attacks argument.

Specified by:

isAttacked in interface ArgumentationFramework<Argument>

Parameters:

argument - an argument

ext - an extension, ie. a set of arguments

Returns:

true if some argument of ext attacks argument.

isAttackedBy

public boolean isAttackedBy(Argument argument,
 Collection<Argument> ext)

returns true if some argument of ext is attacked by argument.

Parameters:

argument - an argument

ext - an extension, ie. a set of arguments

Returns:

true if some argument of ext is attacked by argument.

isAttacked

public boolean isAttacked(Extension<DungTheory> ext1,
 Extension<DungTheory> ext2)

returns true if some argument of ext2 attacks some argument in ext1

Parameters:

ext1 - an extension, ie. a set of arguments

ext2 - an extension, ie. a set of arguments

Returns:

true if some argument of ext2 attacks some argument in ext1

isStable

public boolean isStable(Extension<DungTheory> e)

Checks whether the given extension is stable wrt. this theory.

Parameters:

e - some extension

Returns:

"true" iff the extension is stable.

isPreferred

public boolean isPreferred(Extension<DungTheory> e)

Checks whether the given extension is preferred wrt. this theory.

Parameters:

e - some extension

Returns:

"true" iff the extension is preferred.

isComplete

public boolean isComplete(Extension<DungTheory> e)

Checks whether the given extension is complete wrt. this theory.

Parameters:

e - some extension

Returns:

"true" iff the extension is complete.

faf

public Extension<DungTheory> faf(Extension<DungTheory> extension)

The characteristic function of an abstract argumentation framework: F_AF(S) = {A|A is acceptable wrt. S}.

Parameters:

extension - an extension (a set of arguments).

Returns:

an extension (a set of arguments).

isAttackedBy

public boolean isAttackedBy(Argument arg1,
 Argument arg2)

Checks whether arg1 is attacked by arg2.

Parameters:

arg1 - an argument.

arg2 - an argument.

Returns:

"true" if arg1 is attacked by arg2

isIndirectAttack

public boolean isIndirectAttack(Argument arg1,
 Argument arg2)

Checks whether "arg1" indirectly attacks "arg2", i.e. whether there is an odd-length path from "arg1" to "arg2".

Parameters:

arg1 - an AbstractArgument.

arg2 - an AbstractArgument.

Returns:

"true" iff "arg1" indirectly attacks "arg2".

isSupport

public boolean isSupport(Argument arg1,
 Argument arg2)

Checks whether "arg1" supports "arg2", i.e. whether there is an even-length path from "arg1" to "arg2".

Parameters:

arg1 - an AbstractArgument.

arg2 - an AbstractArgument.

Returns:

"true" iff "arg1" supports "arg2".

isAttackBranch

public boolean isAttackBranch(Argument a,
 Argument b)

Checks whether the path from b to a is an attack branch, i.e. whether b is a non-attacked (indirect) attacker of a.

Parameters:

a - an Argument

b - an Argument

Returns:

true iff the path from a to b is an attack branch, false otherwise

isDefenseBranch

public boolean isDefenseBranch(Argument a,
 Argument b)

Checks whether the path from b to a is a defense branch, i.e. whether b is a non-attacked (indirect) defender of a.

Parameters:

a - an Argument

b - an Argument

Returns:

true iff the path from a to b is a defense branch, false otherwise

hasAttackBranch

public boolean hasAttackBranch(Argument a)

If this graph is acyclic, this method checks if the given argument has an attack branch, i.e. if it is (indirectly) attacked by a non-attacked argument.

Parameters:

a - an Argument

Returns:

true iff this graph is acyclic and a has an attack branch, false otherwise

hasDefenseBranch

public boolean hasDefenseBranch(Argument a)

If this graph is acyclic, this method checks if the given argument has a defense branch, i.e. if it is supported by a non-attacked argument.

Parameters:

a - an Argument

Returns:

true iff this graph is acyclic and a has a defense branch, false otherwise

getUndefendedAttacks

public Collection<Attack> getUndefendedAttacks(Collection<Argument> ext)

Returns the set of attacks (b,a) such that a is in ext and there is no c in ext such that (c,b) is an attack.

Parameters:

ext - some set of arguments.

Returns:

the set of attacks (b,a) such that a is in ext and there is no c in ext such that (c,b) is an attack.

getUnattackedAttackers

public Collection<Argument> getUnattackedAttackers(Collection<Argument> ext)

Returns the set of arguments b such that a is in ext and there is no c in ext such that (c,b) is an attack.

Parameters:

ext - some set of arguments.

Returns:

the set of arguments b such that a is in ext and there is no c in ext such that (c,b) is an attack.

prettyPrint

public String prettyPrint()

Pretty print of the theory.

Returns:

the pretty print of the theory.

toString

public String toString()

Specified by:

toString in interface BeliefBase

Specified by:

toString in interface Graph<Argument>

Overrides:

toString in class BeliefSet<Argument, DungSignature>

add

public boolean add(Attack attack)

Adds the given attack to this dung theory.

Parameters:

attack - an attack

Returns:

"true" if the set of attacks has been modified.

add

public boolean add(Attack... attacks)

Adds the given attacks to this dung theory.

Parameters:

attacks - some attacks

Returns:

"true" if the set of attacks has been modified.

addAttack

public boolean addAttack(Argument attacker,
 Argument attacked)

Adds an attack from the first argument to the second to thisDdung theory.

Parameters:

attacker - some argument

attacked - some argument

Returns:

"true" if the set of attacks has been modified.

remove

public boolean remove(Attack attack)

Removes the given attack from this Dung theory.

Parameters:

attack - an attack

Returns:

"true" if the set of attacks has been modified.

remove

public boolean remove(Argument a)

Removes the argument and all its attacks

Parameters:

a - some argument

Returns:

true if this structure has been changed

removeAll

public boolean removeAll(Collection<?> c)

Specified by:

removeAll in interface Collection<Argument>

Overrides:

removeAll in class BeliefSet<Argument, DungSignature>

contains

public boolean contains(Object o)

Description copied from interface: Graph

Returns "true" when this graph contains the given node or edge.

Specified by:

contains in interface Collection<Argument>

Specified by:

contains in interface Graph<Argument>

Overrides:

contains in class BeliefSet<Argument, DungSignature>

Parameters:

o - an object

Returns:

"true" if this graph contains the given node or edge.

containsAll

public boolean containsAll(Collection<?> c)

Description copied from interface: ArgumentationFramework

Checks if the argumentation framework contains all the elements in the given collection.

Specified by:

containsAll in interface ArgumentationFramework<Argument>

Specified by:

containsAll in interface Collection<Argument>

Overrides:

containsAll in class BeliefSet<Argument, DungSignature>

Parameters:

c - the collection of elements to be checked for containment.

Returns:

true if this framework contains all elements in the specified collection, false otherwise.

containsAttack

public boolean containsAttack(Attack att)

Checks whether this theory contains the given attack.

Parameters:

att - some attack

Returns:

"true" iff this theory contains the given attack.

addAllAttacks

public boolean addAllAttacks(Collection<? extends Attack> c)

Adds the set of attacks to this Dung theory.

Parameters:

c - a collection of attacks

Returns:

"true" if this Dung theory has been modified.

add

public boolean add(DungTheory theory)

Adds all arguments and attacks of the given theory to this theory

Parameters:

theory - some Dung theory

Returns:

"true" if this Dung Theory has been modified

add

public boolean add(Argument argument)

Description copied from interface: Graph

Adds the given node to this graph.

Specified by:

add in interface Collection<Argument>

Specified by:

add in interface Graph<Argument>

Overrides:

add in class BeliefSet<Argument, DungSignature>

Parameters:

argument - some node.

Returns:

"true" iff the edge has been added successfully.

getAttacks

public Set<Attack> getAttacks()

Returns all attacks of this theory.

Returns:

all attacks of this theory.

getBidirectionalAttacks

public Set<Attack> getBidirectionalAttacks()

Returns all bidirectional attacks of this theory.

Returns:

all bidirectional attacks of this theory.

getRestriction

public Graph<Argument> getRestriction(Collection<Argument> arguments)

Description copied from interface: GeneralGraph

Returns a copy of this graph that contains only the specified nodes and all corresponding edges between them.

This method generates a subgraph (or restricted graph) from the current graph by including only the given nodes and the edges that connect them. The returned graph is a new instance and does not modify the original graph.

Specified by:

getRestriction in interface GeneralGraph<Argument>

Parameters:

arguments - a collection of nodes to be included in the restricted graph.

Returns:

a `GeneralGraph` object representing the restricted graph.

getReduct

public DungTheory getReduct(Collection<Argument> arguments)

computes the reduct of bbase wrt. ext ie. removes all arguments from bbase which are either in ext or are attacked by any element of ext

Parameters:

arguments - the arguments

Returns:

the reduct

getReduct

public DungTheory getReduct(Argument arg)

computes the reduct of this wrt. arg ie. removes arg and all arguments attacked by arg

Parameters:

arg - some argument

Returns:

the reduct

hashCode

public int hashCode()

Specified by:

hashCode in interface Collection<Argument>

Overrides:

hashCode in class BeliefSet<Argument, DungSignature>

equals

public boolean equals(Object obj)

Specified by:

equals in interface Collection<Argument>

Overrides:

equals in class BeliefSet<Argument, DungSignature>

add

public boolean add(GeneralEdge<Argument> edge)

Description copied from interface: Graph

Adds the given edge to this graph. If at least one of the nodes the given edge connects is not in the graph, an illegal argument exception is thrown.

Specified by:

add in interface Graph<Argument>

Parameters:

edge - some edge.

Returns:

"true" iff the edge has been added successfully.

getNodes

public Collection<Argument> getNodes()

Description copied from interface: Graph

Returns the nodes of this graph.

Specified by:

getNodes in interface ArgumentationFramework<Argument>

Specified by:

getNodes in interface GeneralGraph<Argument>

Specified by:

getNodes in interface Graph<Argument>

Returns:

the nodes of this graph.

getNumberOfNodes

public int getNumberOfNodes()

Description copied from interface: Graph

Returns the number of nodes in this graph.

Specified by:

getNumberOfNodes in interface Graph<Argument>

Returns:

the number of nodes in this graph.

areAdjacent

public boolean areAdjacent(Argument a,
 Argument b)

Description copied from interface: Graph

Returns "true" iff the two nodes are connected by a directed edge from a to b or an undirected edge.

Specified by:

areAdjacent in interface Graph<Argument>

Parameters:

a - some node

b - some node

Returns:

"true" iff the two nodes are connected by a directed edge from a to b or an undirected edge.

getEdges

public Collection<? extends Edge<? extends Argument>> getEdges()

Description copied from interface: Graph

Returns the edges of this graph.

Specified by:

getEdges in interface GeneralGraph<Argument>

Specified by:

getEdges in interface Graph<Argument>

Returns:

the edges of this graph.

getChildren

public Collection<Argument> getChildren(Node node)

Description copied from interface: Graph

Returns the set of children (node connected via an undirected edge or a directed edge where the given node is the parent) of the given node.

Specified by:

getChildren in interface Graph<Argument>

Parameters:

node - some node (must be in the graph).

Returns:

the set of children of the given node.

getParents

public Collection<Argument> getParents(Node node)

Description copied from interface: Graph

Returns the set of parents (node connected via an undirected edge or a directed edge where the given node is the child) of the given node.

Specified by:

getParents in interface Graph<Argument>

Parameters:

node - some node (must be in the graph).

Returns:

the set of parents of the given node.

existsDirectedPath

public boolean existsDirectedPath(Argument node1,
 Argument node2)

Description copied from interface: Graph

Checks whether there is a (directed) path from node1 to node2.

Specified by:

existsDirectedPath in interface Graph<Argument>

Parameters:

node1 - some node.

node2 - some node.

Returns:

"true" if there is a directed path from node1 to node2.

getNeighbors

public Collection<Argument> getNeighbors(Argument node)

Description copied from interface: Graph

Returns the set of neighbors of the given node.

Specified by:

getNeighbors in interface Graph<Argument>

Parameters:

node - some node (must be in the graph).

Returns:

the set of neighbors of the given node.

getAdjacencyMatrix

public Matrix getAdjacencyMatrix()

Description copied from interface: Graph

Returns the adjacency matrix of this graph (the order of the nodes is the same as returned by "iterator()").

Specified by:

getAdjacencyMatrix in interface Graph<Argument>

Returns:

the adjacency matrix of this graph

getComplementGraph

public DungTheory getComplementGraph(int selfloops)

Description copied from interface: Graph

Returns the complement graph of this graph, i.e. the graph on the same set of vertices as this graph that connects two vertices v and w with an edge if and only if v and w are not connected in this graph.

Specified by:

getComplementGraph in interface Graph<Argument>

Parameters:

selfloops - Indicates how to deal with selfloops:
IGNORE_SELFLOOPS - ignore self loops (don't add and don't remove)
INVERT_SELFLOOPS - deal with self loops like ordinary edges (add if not present and remove if present)
REMOVE_SELFLOOPS - simple remove self loops, but don't add new ones.

Returns:

the complement graph of this graph.

hasSelfLoops

public boolean hasSelfLoops()

Description copied from interface: Graph

Returns "true" iff the graph has a self loop (an edge from a node to itself).

Specified by:

hasSelfLoops in interface Graph<Argument>

Returns:

"true" iff the graph has a self loop (an edge from a node to itself).

getEdge

public Edge<Argument> getEdge(Argument a,
 Argument b)

Description copied from interface: Graph

Returns the corresponding edge (a,b) if a and b are adjacent. Otherwise it returns null.

Specified by:

getEdge in interface Graph<Argument>

Parameters:

a - some node

b - some node

Returns:

the edge (a,b) or null.

isWeightedGraph

public boolean isWeightedGraph()

Description copied from interface: Graph

Checks whether this graph only contains weighted edges.

Specified by:

isWeightedGraph in interface Graph<Argument>

Returns:

"true" if all edges are weighted in this graph.

getConnectedComponents

public Collection<Collection<Argument>> getConnectedComponents()

Description copied from interface: Graph

Returns the set of (simple) connected components of this graph. A set of nodes is connected, if there is some path (ignoring edge directions) from each node to each other. It is a connected component if it is connected and maximal wrt. set inclusion.

Specified by:

getConnectedComponents in interface Graph<Argument>

Returns:

the connected components of this graph.

getStronglyConnectedComponents

public Collection<Collection<Argument>> getStronglyConnectedComponents()

Description copied from interface: Graph

Returns the strongly connected components of this graph. A set of nodes is strongly connected, if there is a path from each node to each other. A set of nodes is called strongly connected component if it is strongly connected and maximal with respect to set inclusion.

Specified by:

getStronglyConnectedComponents in interface Graph<Argument>

Returns:

the strongly connected components of this graph.

getSubgraphs

public Collection<Graph<Argument>> getSubgraphs()

Description copied from interface: Graph

Returns the set of sub graphs of this graph.

Specified by:

getSubgraphs in interface Graph<Argument>

Returns:

the set of sub graphs of this graph.

compareTo

public int compareTo(DungTheory o)

Specified by:

compareTo in interface Comparable<DungTheory>

containsCycle

public <S extends Node> boolean containsCycle()

Checks whether there is at least one cycle in this DungTheory.

Type Parameters:

S - the type of nodes

Returns:

"true" if there is a cycle in this DungTheory, "false" otherwise

containsOddCycle

public <S extends Node> boolean containsOddCycle()

Checks whether there is at least on eodd cycle in this DungTheory. A directed graph has an odd-length cycle if and only if at least one of its SCCs is non-bipartite

Type Parameters:

S - the type of nodes

Returns:

"true" if there is a cycle with odd length in this theory

getComponents

public Collection<Graph<Argument>> getComponents()

Returns:

DefaultGraph

getInducedSubgraphs

public Collection<Graph<Argument>> getInducedSubgraphs()

Returns:

DefaultGraph

equalsIn

public boolean equalsIn(HashSet<DungTheory> setOfEquals)

Method to check if an equal object to this object is contained in the specified set

Parameters:

setOfEquals - Set of object of the same class

Returns:

TRUE iff an equal object is contained in the specified set

getNumberOfEdges

public int getNumberOfEdges()

Description copied from interface: Graph

Returns the number of edges in this graph.

Specified by:

getNumberOfEdges in interface Graph<Argument>

Returns:

the number of edges in this graph.