java.lang.Object
org.jgrapht.alg.drawing.BaseLayoutAlgorithm2D<V,E>
org.jgrapht.alg.drawing.FRLayoutAlgorithm2D<V,E>
org.jgrapht.alg.drawing.IndexedFRLayoutAlgorithm2D<V,E>
- Type Parameters:
V
- the graph vertex typeE
- the graph edge type
- All Implemented Interfaces:
LayoutAlgorithm2D<V,
E>
Fruchterman and Reingold Force-Directed Placement Algorithm using the
Barnes-Hut indexing
technique with a QuadTree.
The Barnes-Hut indexing technique is described in the following paper:
- J. Barnes and P. Hut. A hierarchical O(N log N) force-calculation algorithm. Nature. 324(4):446--449, 1986.
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Nested Class Summary
Nested classes/interfaces inherited from class org.jgrapht.alg.drawing.FRLayoutAlgorithm2D
FRLayoutAlgorithm2D.InverseLinearTemperatureModel, FRLayoutAlgorithm2D.TemperatureModel
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Field Summary
FieldsModifier and TypeFieldDescriptionstatic final double
Default $\theta$ value for approximation using the Barnes-Hut techniqueprotected long
protected double
Fields inherited from class org.jgrapht.alg.drawing.FRLayoutAlgorithm2D
comparator, DEFAULT_ITERATIONS, DEFAULT_NORMALIZATION_FACTOR, iterations, normalizationFactor, optimalDistance, rng, temperatureModelSupplier
Fields inherited from class org.jgrapht.alg.drawing.BaseLayoutAlgorithm2D
initializer
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Constructor Summary
ConstructorsConstructorDescriptionCreate a new layout algorithmIndexedFRLayoutAlgorithm2D
(int iterations, double theta) Create a new layout algorithmIndexedFRLayoutAlgorithm2D
(int iterations, double theta, double normalizationFactor) Create a new layout algorithmIndexedFRLayoutAlgorithm2D
(int iterations, double theta, double normalizationFactor, Random rng) Create a new layout algorithmIndexedFRLayoutAlgorithm2D
(int iterations, double theta, double normalizationFactor, Random rng, double tolerance) Create a new layout algorithm -
Method Summary
Modifier and TypeMethodDescriptioncalculateRepulsiveForces
(Graph<V, E> graph, LayoutModel2D<V> model) Calculate the repulsive forces between verticeslong
Get the total number of saved comparisons due to the Barnes-Hut technique.void
Layout a graph.Methods inherited from class org.jgrapht.alg.drawing.FRLayoutAlgorithm2D
attractiveForce, calculateAttractiveForces, repulsiveForce
Methods inherited from class org.jgrapht.alg.drawing.BaseLayoutAlgorithm2D
getInitializer, init, setInitializer
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Field Details
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DEFAULT_THETA_FACTOR
public static final double DEFAULT_THETA_FACTORDefault $\theta$ value for approximation using the Barnes-Hut technique- See Also:
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theta
protected double theta -
savedComparisons
protected long savedComparisons
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Constructor Details
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IndexedFRLayoutAlgorithm2D
public IndexedFRLayoutAlgorithm2D()Create a new layout algorithm -
IndexedFRLayoutAlgorithm2D
public IndexedFRLayoutAlgorithm2D(int iterations, double theta) Create a new layout algorithm- Parameters:
iterations
- number of iterationstheta
- parameter for approximation using the Barnes-Hut technique
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IndexedFRLayoutAlgorithm2D
public IndexedFRLayoutAlgorithm2D(int iterations, double theta, double normalizationFactor) Create a new layout algorithm- Parameters:
iterations
- number of iterationstheta
- parameter for approximation using the Barnes-Hut techniquenormalizationFactor
- normalization factor for the optimal distance
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IndexedFRLayoutAlgorithm2D
public IndexedFRLayoutAlgorithm2D(int iterations, double theta, double normalizationFactor, Random rng) Create a new layout algorithm- Parameters:
iterations
- number of iterationstheta
- theta parameter for the Barnes-Hut approximationnormalizationFactor
- normalization factor for the optimal distancerng
- the random number generator
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IndexedFRLayoutAlgorithm2D
public IndexedFRLayoutAlgorithm2D(int iterations, double theta, double normalizationFactor, Random rng, double tolerance) Create a new layout algorithm- Parameters:
iterations
- number of iterationstheta
- theta parameter for the Barnes-Hut approximationnormalizationFactor
- normalization factor for the optimal distancerng
- the random number generatortolerance
- tolerance used when comparing floating point values
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Method Details
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layout
Description copied from interface:LayoutAlgorithm2D
Layout a graph.- Specified by:
layout
in interfaceLayoutAlgorithm2D<V,
E> - Overrides:
layout
in classFRLayoutAlgorithm2D<V,
E> - Parameters:
graph
- the graphmodel
- the layout model to use
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calculateRepulsiveForces
Description copied from class:FRLayoutAlgorithm2D
Calculate the repulsive forces between vertices- Overrides:
calculateRepulsiveForces
in classFRLayoutAlgorithm2D<V,
E> - Parameters:
graph
- the graphmodel
- the model- Returns:
- the displacement per vertex due to the repulsive forces
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getSavedComparisons
public long getSavedComparisons()Get the total number of saved comparisons due to the Barnes-Hut technique.- Returns:
- the total number of saved comparisons
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