ogdf::GEMLayout Class Reference

The energy-based GEM layout algorithm. More...

#include <ogdf/energybased/GEMLayout.h>

Inheritance diagram for ogdf::GEMLayout:

Public Member Functions
	GEMLayout ()
	Creates an instance of GEM layout.
	GEMLayout (const GEMLayout &fl)
	Copy constructor.
	~GEMLayout ()
int	attractionFormula () const
	Returns the used formula for attraction (1 = Fruchterman / Reingold, 2 = GEM).
void	attractionFormula (int n)
	sets the formula for attraction to n (1 = Fruchterman / Reingold, 2 = GEM).
virtual void	call (GraphAttributes &GA) override
	Calls the layout algorithm for graph attributes GA.
double	desiredLength () const
	Returns the desired edge length.
void	desiredLength (double x)
	Sets the desired edge length to x; must be >= 0.
double	gravitationalConstant () const
	Returns the gravitational constant.
void	gravitationalConstant (double x)
	Sets the gravitational constant to x; must be >= 0. Attention! Only (very) small values give acceptable results.
double	initialTemperature () const
	Returns the initial temperature.
void	initialTemperature (double x)
	Sets the initial temperature to x; must be >= minimalTemperature.
double	maximalDisturbance () const
	Returns the maximal disturbance.
void	maximalDisturbance (double x)
	Sets the maximal disturbance to x; must be >= 0.
double	minDistCC () const
	Returns the minimal distance between connected components.
void	minDistCC (double x)
	Sets the minimal distance between connected components to x.
double	minimalTemperature () const
	Returns the minimal temperature.
void	minimalTemperature (double x)
	Sets the minimal temperature to x.
int	numberOfRounds () const
	Returns the maximal number of rounds per node.
void	numberOfRounds (int n)
	Sets the maximal number of round per node to n.
GEMLayout &	operator= (const GEMLayout &fl)
	Assignment operator.
double	oscillationAngle () const
	Returns the opening angle for oscillations.
void	oscillationAngle (double x)
	Sets the opening angle for oscillations to x (0 <= x <= pi / 2).
double	oscillationSensitivity () const
	Returns the oscillation sensitivity.
void	oscillationSensitivity (double x)
	Sets the oscillation sensitivity to x (0 <= x <= 1).
double	pageRatio () const
	Returns the page ratio used for the layout of connected components.
void	pageRatio (double x)
	Sets the page ratio used for the layout of connected components to x.
double	rotationAngle () const
	Returns the opening angle for rotations.
void	rotationAngle (double x)
	Sets the opening angle for rotations to x (0 <= x <= pi / 2).
double	rotationSensitivity () const
	Returns the rotation sensitivity.
void	rotationSensitivity (double x)
	Sets the rotation sensitivity to x (0 <= x <= 1).
Public Member Functions inherited from ogdf::LayoutModule
	LayoutModule ()
	Initializes a layout module.
virtual	~LayoutModule ()
void	operator() (GraphAttributes &GA)
	Computes a layout of graph GA.

Private Member Functions
void	computeImpulse (GraphCopy &GC, GraphAttributes &AGC, node v)
	Computes the new impulse for node v.
double	length (double x, double y=0) const
	Returns the length of the vector (x,y).
void	updateNode (GraphCopy &GC, GraphAttributes &AGC, node v)
	Updates the node data for node v.
double	weight (node v) const
	Returns the weight of node v according to its degree.

Private Attributes
int	m_attractionFormula
	The used formula for attraction.
double	m_barycenterX
	Weighted sum of x-coordinates of all nodes.
double	m_barycenterY
	Weighted sum of y-coordinates of all nodes.
double	m_cos
	Cosine of m_oscillationAngle / 2.
double	m_desiredLength
	The desired edge length.
double	m_globalTemperature
	Average of all node temperatures.
double	m_gravitationalConstant
	The gravitational constant.
NodeArray< double >	m_impulseX
	x-coordinate of the last impulse of the node
NodeArray< double >	m_impulseY
	y-coordinate of the last impulse of the node
double	m_initialTemperature
	The initial temperature.
NodeArray< double >	m_localTemperature
	local temperature of the node
double	m_maximalDisturbance
	The maximal disturbance.
double	m_minDistCC
	The minimal distance between connected components.
double	m_minimalTemperature
	The minimal temperature.
double	m_newImpulseX
	x-coordinate of the new impulse of the current node.
double	m_newImpulseY
	y-coordinate of the new impulse of the current node.
int	m_numberOfRounds
	The maximal number of rounds per node.
double	m_oscillationAngle
	The opening angle for oscillations.
double	m_oscillationSensitivity
	The oscillation sensitivity.
double	m_pageRatio
	The page ratio used for the layout of connected components.
std::minstd_rand	m_rng
double	m_rotationAngle
	The opening angle for rotations.
double	m_rotationSensitivity
	The rotation sensitivity.
double	m_sin
	Sine of (pi + m_rotationAngle) / 2.
NodeArray< double >	m_skewGauge
	skew gauge of the node

Detailed Description

The energy-based GEM layout algorithm.

The implementation used in GEMLayout is based on the following publication:

Arne Frick, Andreas Ludwig, Heiko Mehldau: A Fast Adaptive Layout Algorithm for Undirected Graphs. Proc. Graph Drawing 1994, LNCS 894, pp. 388-403, 1995.

Optional parameters

GEM layout provides the following optional parameters.

Option	Type	Default	Description
numberOfRounds	int	20000	The maximal number of rounds per node.
minimalTemperature	double	0.005	The minimal temperature.
initialTemperature	double	10.0	The initial temperature.
gravitationalConstant	double	1/16	The gravitational constant.
desiredLength	double	5.0	The desired edge length.
maximalDisturbance	double	0	The maximal disturbance.
rotationAngle	double	pi/3.0	The opening angle for rotations.
oscillationAngle	double	pi/2.0	The opening angle for oscillations.
rotationSensitivity	double	0.01	The rotation sensitivity.
oscillationSensitivity	double	0.3	The oscillation sensitivity.
attractionFormula	int	1	The used formula for attraction (1 = Fruchterman / Reingold, 2 = GEM).
minDistCC	double	20	The minimal distance between connected components.
pageRatio	double	1.0	The page ratio used for the layout of connected components.

Definition at line 104 of file GEMLayout.h.

Constructor & Destructor Documentation

GEMLayout() [1/2]

ogdf::GEMLayout::GEMLayout

(

)

Creates an instance of GEM layout.

GEMLayout() [2/2]

ogdf::GEMLayout::GEMLayout

(

const GEMLayout &

fl

)

Copy constructor.

~GEMLayout()

ogdf::GEMLayout::~GEMLayout

(

)

Member Function Documentation

attractionFormula() [1/2]

int ogdf::GEMLayout::attractionFormula ( ) const

inline

Returns the used formula for attraction (1 = Fruchterman / Reingold, 2 = GEM).

Definition at line 252 of file GEMLayout.h.

attractionFormula() [2/2]

void ogdf::GEMLayout::attractionFormula ( int  n )

inline

sets the formula for attraction to n (1 = Fruchterman / Reingold, 2 = GEM).

Definition at line 255 of file GEMLayout.h.

call()

virtual void ogdf::GEMLayout::call ( GraphAttributes &  GA )

overridevirtual

Calls the layout algorithm for graph attributes GA.

Implements ogdf::LayoutModule.

computeImpulse()

void ogdf::GEMLayout::computeImpulse ( GraphCopy &  GC, GraphAttributes &  AGC, node  v  )

private

Computes the new impulse for node v.

desiredLength() [1/2]

double ogdf::GEMLayout::desiredLength ( ) const

inline

Returns the desired edge length.

Definition at line 184 of file GEMLayout.h.

desiredLength() [2/2]

void ogdf::GEMLayout::desiredLength ( double  x )

inline

Sets the desired edge length to x; must be >= 0.

Definition at line 187 of file GEMLayout.h.

gravitationalConstant() [1/2]

double ogdf::GEMLayout::gravitationalConstant ( ) const

inline

Returns the gravitational constant.

Definition at line 177 of file GEMLayout.h.

gravitationalConstant() [2/2]

void ogdf::GEMLayout::gravitationalConstant ( double  x )

inline

Sets the gravitational constant to x; must be >= 0. Attention! Only (very) small values give acceptable results.

Definition at line 181 of file GEMLayout.h.

initialTemperature() [1/2]

double ogdf::GEMLayout::initialTemperature ( ) const

inline

Returns the initial temperature.

Definition at line 169 of file GEMLayout.h.

initialTemperature() [2/2]

void ogdf::GEMLayout::initialTemperature ( double  x )

inline

Sets the initial temperature to x; must be >= minimalTemperature.

Definition at line 172 of file GEMLayout.h.

length()

double ogdf::GEMLayout::length ( double  x, double  y = 0  ) const

inlineprivate

Returns the length of the vector (x,y).

Definition at line 276 of file GEMLayout.h.

maximalDisturbance() [1/2]

double ogdf::GEMLayout::maximalDisturbance ( ) const

inline

Returns the maximal disturbance.

Definition at line 190 of file GEMLayout.h.

maximalDisturbance() [2/2]

void ogdf::GEMLayout::maximalDisturbance ( double  x )

inline

Sets the maximal disturbance to x; must be >= 0.

Definition at line 193 of file GEMLayout.h.

minDistCC() [1/2]

double ogdf::GEMLayout::minDistCC ( ) const

inline

Returns the minimal distance between connected components.

Definition at line 262 of file GEMLayout.h.

minDistCC() [2/2]

void ogdf::GEMLayout::minDistCC ( double  x )

inline

Sets the minimal distance between connected components to x.

Definition at line 265 of file GEMLayout.h.

minimalTemperature() [1/2]

double ogdf::GEMLayout::minimalTemperature ( ) const

inline

Returns the minimal temperature.

Definition at line 163 of file GEMLayout.h.

minimalTemperature() [2/2]

void ogdf::GEMLayout::minimalTemperature ( double  x )

inline

Sets the minimal temperature to x.

Definition at line 166 of file GEMLayout.h.

numberOfRounds() [1/2]

int ogdf::GEMLayout::numberOfRounds ( ) const

inline

Returns the maximal number of rounds per node.

Definition at line 157 of file GEMLayout.h.

numberOfRounds() [2/2]

void ogdf::GEMLayout::numberOfRounds ( int  n )

inline

Sets the maximal number of round per node to n.

Definition at line 160 of file GEMLayout.h.

operator=()

GEMLayout & ogdf::GEMLayout::operator=

(

const GEMLayout &

fl

)

Assignment operator.

oscillationAngle() [1/2]

double ogdf::GEMLayout::oscillationAngle ( ) const

inline

Returns the opening angle for oscillations.

Definition at line 210 of file GEMLayout.h.

oscillationAngle() [2/2]

void ogdf::GEMLayout::oscillationAngle ( double  x )

inline

Sets the opening angle for oscillations to x (0 <= x <= pi / 2).

Definition at line 213 of file GEMLayout.h.

oscillationSensitivity() [1/2]

double ogdf::GEMLayout::oscillationSensitivity ( ) const

inline

Returns the oscillation sensitivity.

Definition at line 238 of file GEMLayout.h.

oscillationSensitivity() [2/2]

void ogdf::GEMLayout::oscillationSensitivity ( double  x )

inline

Sets the oscillation sensitivity to x (0 <= x <= 1).

Definition at line 241 of file GEMLayout.h.

pageRatio() [1/2]

double ogdf::GEMLayout::pageRatio ( ) const

inline

Returns the page ratio used for the layout of connected components.

Definition at line 268 of file GEMLayout.h.

pageRatio() [2/2]

void ogdf::GEMLayout::pageRatio ( double  x )

inline

Sets the page ratio used for the layout of connected components to x.

Definition at line 271 of file GEMLayout.h.

rotationAngle() [1/2]

double ogdf::GEMLayout::rotationAngle ( ) const

inline

Returns the opening angle for rotations.

Definition at line 196 of file GEMLayout.h.

rotationAngle() [2/2]

void ogdf::GEMLayout::rotationAngle ( double  x )

inline

Sets the opening angle for rotations to x (0 <= x <= pi / 2).

Definition at line 199 of file GEMLayout.h.

rotationSensitivity() [1/2]

double ogdf::GEMLayout::rotationSensitivity ( ) const

inline

Returns the rotation sensitivity.

Definition at line 224 of file GEMLayout.h.

rotationSensitivity() [2/2]

void ogdf::GEMLayout::rotationSensitivity ( double  x )

inline

Sets the rotation sensitivity to x (0 <= x <= 1).

Definition at line 227 of file GEMLayout.h.

updateNode()

void ogdf::GEMLayout::updateNode ( GraphCopy &  GC, GraphAttributes &  AGC, node  v  )

private

Updates the node data for node v.

weight()

double ogdf::GEMLayout::weight ( node  v ) const

inlineprivate

Returns the weight of node v according to its degree.

Definition at line 279 of file GEMLayout.h.

Member Data Documentation

m_attractionFormula

int ogdf::GEMLayout::m_attractionFormula

private

The used formula for attraction.

Definition at line 117 of file GEMLayout.h.

m_barycenterX

double ogdf::GEMLayout::m_barycenterX

private

Weighted sum of x-coordinates of all nodes.

Definition at line 130 of file GEMLayout.h.

m_barycenterY

double ogdf::GEMLayout::m_barycenterY

private

Weighted sum of y-coordinates of all nodes.

Definition at line 131 of file GEMLayout.h.

m_cos

double ogdf::GEMLayout::m_cos

private

Cosine of m_oscillationAngle / 2.

Definition at line 135 of file GEMLayout.h.

m_desiredLength

double ogdf::GEMLayout::m_desiredLength

private

The desired edge length.

Definition at line 111 of file GEMLayout.h.

m_globalTemperature

double ogdf::GEMLayout::m_globalTemperature

private

Average of all node temperatures.

Definition at line 134 of file GEMLayout.h.

m_gravitationalConstant

double ogdf::GEMLayout::m_gravitationalConstant

private

The gravitational constant.

Definition at line 110 of file GEMLayout.h.

m_impulseX

NodeArray<double> ogdf::GEMLayout::m_impulseX

private

x-coordinate of the last impulse of the node

Definition at line 123 of file GEMLayout.h.

m_impulseY

NodeArray<double> ogdf::GEMLayout::m_impulseY

private

y-coordinate of the last impulse of the node

Definition at line 124 of file GEMLayout.h.

m_initialTemperature

double ogdf::GEMLayout::m_initialTemperature

private

The initial temperature.

Definition at line 109 of file GEMLayout.h.

m_localTemperature

NodeArray<double> ogdf::GEMLayout::m_localTemperature

private

local temperature of the node

Definition at line 125 of file GEMLayout.h.

m_maximalDisturbance

double ogdf::GEMLayout::m_maximalDisturbance

private

The maximal disturbance.

Definition at line 112 of file GEMLayout.h.

m_minDistCC

double ogdf::GEMLayout::m_minDistCC

private

The minimal distance between connected components.

Definition at line 118 of file GEMLayout.h.

m_minimalTemperature

double ogdf::GEMLayout::m_minimalTemperature

private

The minimal temperature.

Definition at line 108 of file GEMLayout.h.

m_newImpulseX

double ogdf::GEMLayout::m_newImpulseX

private

x-coordinate of the new impulse of the current node.

Definition at line 132 of file GEMLayout.h.

m_newImpulseY

double ogdf::GEMLayout::m_newImpulseY

private

y-coordinate of the new impulse of the current node.

Definition at line 133 of file GEMLayout.h.

m_numberOfRounds

int ogdf::GEMLayout::m_numberOfRounds

private

The maximal number of rounds per node.

Definition at line 107 of file GEMLayout.h.

m_oscillationAngle

double ogdf::GEMLayout::m_oscillationAngle

private

The opening angle for oscillations.

Definition at line 114 of file GEMLayout.h.

m_oscillationSensitivity

double ogdf::GEMLayout::m_oscillationSensitivity

private

The oscillation sensitivity.

Definition at line 116 of file GEMLayout.h.

m_pageRatio

double ogdf::GEMLayout::m_pageRatio

private

The page ratio used for the layout of connected components.

Definition at line 119 of file GEMLayout.h.

m_rng

std::minstd_rand ogdf::GEMLayout::m_rng

private

Definition at line 138 of file GEMLayout.h.

m_rotationAngle

double ogdf::GEMLayout::m_rotationAngle

private

The opening angle for rotations.

Definition at line 113 of file GEMLayout.h.

m_rotationSensitivity

double ogdf::GEMLayout::m_rotationSensitivity

private

The rotation sensitivity.

Definition at line 115 of file GEMLayout.h.

m_sin

double ogdf::GEMLayout::m_sin

private

Sine of (pi + m_rotationAngle) / 2.

Definition at line 136 of file GEMLayout.h.

m_skewGauge

NodeArray<double> ogdf::GEMLayout::m_skewGauge

private

skew gauge of the node

Definition at line 126 of file GEMLayout.h.

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The documentation for this class was generated from the following file:

• include/ogdf/energybased/GEMLayout.h