Class AbstractNetwork

Object

AbstractGeometry

AbstractNetwork

Direct Known Subclasses:

BarabasiAlbertGeometry, KlemmEguiluzGeometry, RandomRegularGeometry, ScalefreeGeometry

public abstract class AbstractNetwork
extends AbstractGeometry

Base class for geometries constructed from specific degree distributions.

Field Summary

Fields

Modifier and Type	Field	Description
(package private) static final int	MAX_TRIALS	Number of attempts before giving up on constructing the desired graph.
(package private) RNGDistribution	rng	The random number generator distribution used for network construction.

Fields inherited from class AbstractGeometry

connectivity, EMPTY_LINKS, engine, features, in, isInterspecies, isRegular, isRewired, isSingle, isUndirected, isValid, kin, kout, logger, name, network2D, network3D, out, pAddwire, pRewire, size, specs, type

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	AbstractNetwork(EvoLudo engine)	Create a network-backed geometry for the provided engine.

Method Summary

Modifier and Type	Method	Description
private int	buildConnectedCore(int[] core, int[] full, int[] degree)	Build a connected core of the network first, excluding leaves.
private int	connectCorePairs(int[] core, int[] full, int[] degree, int remain)	Connect pairs of nodes from the core until no unmatched nodes remain or no further progress can be made.
private boolean	handleSingleUnmatched(int nodea, int[] full)	Handle the case where a single node remains unmatched by breaking an existing edge and reconnecting both endpoints to that final node.
protected boolean	initGeometryDegreeDistr(int[] degree)	Utility method to generate a network that realises the requested degree sequence.
private int[]	initializeCore()	Initialize the core array with all node indices.
private boolean	rewireNeighbourEdge(int nodeA, int nodeB, int[] done, int nDone)	Attempt to rewire existing edges so that nodes nodeA and nodeB can gain additional neighbours without introducing duplicate links.
private boolean	tryConnectOrRewire(int nodea, int nodeb, int[] full, int nFull, int remain)	Attempt to connect two nodes, rewiring existing edges if necessary.
private int	updateProgressAfterConnect(int[] core, int[] full, int[] degree, int remain, int idxa, int idxb)	Update the progress after successfully connecting two nodes.

Methods inherited from class AbstractGeometry

addDirected, addEdgeAt, addLinkAt, addUndirected, alloc, check, checkSettings, clearLinksFrom, clearLinksTo, clone, create, create, decodeGeometry, deriveCompetitionGeometry, displaySingle, encodeGeometry, enforceSize, equals, getAddwire, getConnectivity, getEncodeKey, getFeatures, getLabel, getName, getNetwork2D, getNetwork3D, getRewire, getSize, getSpecs, getType, hashCode, init, isConsistent, isGraphConnected, isInterspecies, isLattice, isNeighborOf, isRegular, isRewired, isSingle, isType, isUndirected, isUnique, parse, parse, removeEdgeAt, removeLinkAt, rewire, rewireDirected, rewireEdgeAt, rewireLinkAt, rewireUndirected, setAddwire, setConnectivity, setInterspecies, setName, setNetwork2D, setNetwork3D, setRewire, setSingle, setSize, setType, swapEdges, usage, warn

Methods inherited from class Object

finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Field Details

MAX_TRIALS

static final int MAX_TRIALS

Number of attempts before giving up on constructing the desired graph.

See Also:

• Constant Field Values

rng

RNGDistribution rng

The random number generator distribution used for network construction.

Constructor Details

AbstractNetwork

protected AbstractNetwork(EvoLudo engine)

Create a network-backed geometry for the provided engine.

Parameters:

engine - the EvoLudo pacemaker

Method Details

initGeometryDegreeDistr

protected boolean initGeometryDegreeDistr(int[] degree)

Utility method to generate a network that realises the requested degree sequence.

Requirements/notes:

1. The degree array is expected to be sorted in descending order.
2. During construction, already connected pairs are rewired via rewireNeighbourEdge(int, int, int[], int) to avoid multiple edges.
3. If a single node remains unmatched, the method attempts to break one of the existing links and reconnect both endpoints to that final node.

Parameters:

degree - the degree (outgoing link count) requested for every node

Returns:

true if a matching graph was constructed successfully

initializeCore

private int[] initializeCore()

Initialize the core array with all node indices.

Returns:

the initialized core array

buildConnectedCore

private int buildConnectedCore(int[] core,
 int[] full,
 int[] degree)

Build a connected core of the network first, excluding leaves.

Parameters:

core - the array of node indices to draw from

full - the array to store completed nodes in

degree - the desired degree sequence

Returns:

the number of remaining nodes in core after building the connected core

connectCorePairs

private int connectCorePairs(int[] core,
 int[] full,
 int[] degree,
 int remain)

Connect pairs of nodes from the core until no unmatched nodes remain or no further progress can be made.

Parameters:

core - the array of node indices to draw from

full - the array to store completed nodes in

degree - the desired degree sequence

remain - the initial number of nodes in core

Returns:

the number of remaining nodes in core after attempting to connect all pairs, or -1 if no progress could be made

tryConnectOrRewire

private boolean tryConnectOrRewire(int nodea,
 int nodeb,
 int[] full,
 int nFull,
 int remain)

Attempt to connect two nodes, rewiring existing edges if necessary.

Parameters:

nodea - the first node to connect

nodeb - the second node to connect

full - the pool of nodes whose desired degrees are already satisfied

nFull - the number of valid entries in full

remain - the number of remaining nodes to connect

Returns:

true if the connection (or rewiring) succeeded

updateProgressAfterConnect

private int updateProgressAfterConnect(int[] core,
 int[] full,
 int[] degree,
 int remain,
 int idxa,
 int idxb)

Update the progress after successfully connecting two nodes.

Parameters:

core - the array of node indices to draw from

full - the array to store completed nodes in

degree - the desired degree sequence

remain - the current number of nodes in core

idxa - the index of the first connected node in core

idxb - the index of the second connected node in core

Returns:

the updated number of nodes remaining in core

handleSingleUnmatched

private boolean handleSingleUnmatched(int nodea,
 int[] full)

Handle the case where a single node remains unmatched by breaking an existing edge and reconnecting both endpoints to that final node.

Parameters:

nodea - the single unmatched node

full - the pool of nodes whose desired degrees are already satisfied

Returns:

true if reconnection succeeded

rewireNeighbourEdge

private boolean rewireNeighbourEdge(int nodeA,
 int nodeB,
 int[] done,
 int nDone)

Attempt to rewire existing edges so that nodes nodeA and nodeB can gain additional neighbours without introducing duplicate links.

Parameters:

nodeA - the first node that still needs neighbours

nodeB - the second node that still needs neighbours

done - the pool of nodes whose desired degrees are already satisfied

nDone - the number of valid entries in done

Returns:

true if rewiring succeeded