edu.uci.ics.jung.algorithms.layout

Class FRLayout2<V,E>

java.lang.Object

edu.uci.ics.jung.algorithms.layout.AbstractLayout<V,E>

edu.uci.ics.jung.algorithms.layout.FRLayout2<V,E>

All Implemented Interfaces:

com.google.common.base.Function<V,java.awt.geom.Point2D>, Layout<V,E>, IterativeContext

public class FRLayout2<V,E>
extends AbstractLayout<V,E>
implements IterativeContext

Implements the Fruchterman-Reingold force-directed algorithm for node layout. This is an experimental attempt at optimizing FRLayout; if it is successful it will be folded back into FRLayout (and this class will disappear).

Behavior is determined by the following settable parameters:

• attraction multiplier: how much edges try to keep their vertices together
• repulsion multiplier: how much vertices try to push each other apart
• maximum iterations: how many iterations this algorithm will use before stopping

Each of the first two defaults to 0.75; the maximum number of iterations defaults to 700.

See Also:

"Fruchterman and Reingold, 'Graph Drawing by Force-directed Placement'", "http://i11www.ilkd.uni-karlsruhe.de/teaching/SS_04/visualisierung/papers/fruchterman91graph.pdf"

Constructor Summary

Constructors

Constructor and Description
FRLayout2(Graph<V,E> g)
FRLayout2(Graph<V,E> g, java.awt.Dimension d)

Method Summary

Modifier and Type	Method and Description
boolean	done()
void	initialize() Initializes fields in the node that may not have been set during the constructor.
boolean	isIncremental()
void	reset()
void	setAttractionMultiplier(double attraction)
void	setMaxIterations(int maxIterations)
void	setRepulsionMultiplier(double repulsion)
void	setSize(java.awt.Dimension size) When a visualization is resized, it presumably wants to fix the locations of the vertices and possibly to reinitialize its data.
void	step() Moves the iteration forward one notch, calculation attraction and repulsion between vertices and edges and cooling the temperature.

Methods inherited from class edu.uci.ics.jung.algorithms.layout.AbstractLayout

apply, getGraph, getSize, getX, getY, isLocked, lock, lock, setGraph, setInitializer, setLocation, setLocation

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.google.common.base.Function

equals

Constructor Detail

FRLayout2

public FRLayout2(Graph<V,E> g)

FRLayout2

public FRLayout2(Graph<V,E> g,
                 java.awt.Dimension d)

Method Detail

setSize

public void setSize(java.awt.Dimension size)

Description copied from class: AbstractLayout

When a visualization is resized, it presumably wants to fix the locations of the vertices and possibly to reinitialize its data. The current method calls initializeLocations followed by initialize_local.

Specified by:

setSize in interface Layout<V,E>

Overrides:

setSize in class AbstractLayout<V,E>

Parameters:

size - the space to use to lay out this graph

setAttractionMultiplier

public void setAttractionMultiplier(double attraction)

setRepulsionMultiplier

public void setRepulsionMultiplier(double repulsion)

reset

public void reset()

Specified by:

reset in interface Layout<V,E>

initialize

public void initialize()

Description copied from interface: Layout

Initializes fields in the node that may not have been set during the constructor. Must be called before the iterations begin.

Specified by:

initialize in interface Layout<V,E>

step

public void step()

Moves the iteration forward one notch, calculation attraction and repulsion between vertices and edges and cooling the temperature.

Specified by:

step in interface IterativeContext

setMaxIterations

public void setMaxIterations(int maxIterations)

isIncremental

public boolean isIncremental()

Returns:

true

done

public boolean done()

Specified by:

done in interface IterativeContext

Returns:

true once the current iteration has passed the maximum count.