PnEnergyMinimizer ("JavaView Reference Manual")

java.lang.Object
- jv.object.PsObject
- - jvx.numeric.PnEnergyMinimizer

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable, java.lang.Runnable, PsUpdateIf
```
public class PnEnergyMinimizer
extends PsObject
implements java.lang.Runnable
```
Main class to vary a surface to minimize a given energy functional. Minimization runs in a separate thread. For Dirichlet and Area minimization support for hessian and eigenvalues included.

See Also:
Serialized Form

Field Summary

Fields
Modifier and Type	Field and Description
`static int`	`ALIGNMENT`
`static int`	`AREA`
`static int`	`CONFORMAL`
`static int`	`DIRICHLET`
`static int`	`GAUSS`
`static int`	`SPRING`
`static int`	`VOLUME`

Fields inherited from class jv.object.PsObject
HAS_BOUNDARY_PANEL, HAS_CONFIG_PANEL, HAS_INFO_PANEL, HAS_LABEL_PANEL, HAS_MATERIAL_PANEL, HAS_TEXTURE_PANEL, HAS_VECTOR_PANEL, INSPECTOR_INFO, INSPECTOR_INFO_EXT, IS_DELETED, IS_FIXED, IS_FOCUSSED, IS_PICKED, IS_SELECTED, IS_USED, NUM_TAGS

Constructor Summary

Constructors
Constructor and Description

PnEnergyMinimizer()

Constructors
Constructor and Description
`PnEnergyMinimizer()`

Method Summary

Methods
Modifier and Type	Method and Description
`int`	`computeEigenvectors()` Compute eigenvectors either of Hessian or of an L2-corrected Hessian.
`void`	`enableUpdateDomain(boolean flag)` Flag whether domain is updated after each CG-minimization loop.
`PgElementSet`	`getDomain()` Get currently registered domain geometry.
`java.lang.String[]`	`getEigenSolver()`
`PsPanel`	`getEigenSolverPanel(int id)`
`PnEnergy`	`getEnergy()` Get current energy.
`double`	`getInitialStepsize()` Get stepsize used in cg iteration.
`PgElementSet`	`getSurface()` Get currently registered surface.
`void`	`init()` If instance has missing name then assign default name 'Object_NUMBER' where number is the total number of already created instances.
`boolean`	`isEnabledConstrainMatrix()` Determine if usage of a constrain matrix is enabled.
`boolean`	`isEnabledFixVertices()` Determine if marked vertices remain fixed during minimization.
`boolean`	`isRunning()` Check whether energy minimizer will be stopped.
`boolean`	`isStopped()` Check whether energy minimizer is currently NOT running a minimizing thread.
`double`	`minimize()` Minimize energy by invoking conjugate gradient method in a loop.
`void`	`printEigenvalues()` Print eigenvalues of hessian to JavaView console.
`void`	`printEigenvectors()` Print eigenvectors of hessian to JavaView console.
`void`	`printGradient()` Evaluate and print the energy gradient to the JavaView console.
`void`	`printHessian()` Evaluate the Hessian matrix of the energy and print its content to the JavaView console.
`void`	`run()` Do energy minimization until `m_numLoops` are done or until a call of stop().
`void`	`saveEigenvectors()` Save eigenvectors of hessian as vector fields of the surface.
`void`	`setEigenSolver(int id)`
`void`	`setEnabledConstrainMatrix(boolean flag)` Enable usage of a constrain matrix for index computation of Neumann boundary geometries.
`void`	`setEnabledFixVertices(boolean flag)` Enable if marked vertices remain fixed during minimization.
`void`	`setEnergy(PnEnergy energy)` Set new energy and clear all vector fields.
`void`	`setInitialStepsize(double h)` Set stepsize used in cg iteration.
`void`	`setNumLoops(int numLoops)` Set number of calls of conjugate gradient method to be performed during each call to PnEnergyMinimizer#minimize().
`boolean`	`setSurface(PgElementSet domain, PgElementSet surface)` Set references to domain and image surface.
`void`	`setUpdateDomain(boolean flag)` Set flag which enables the updating of the domain with the current surface after every minimization step.
`void`	`showEigenvector(int ind)` Show eigenvectors of hessian as vector field on the surface.
`void`	`showGradient()` Evaluate and show the gradient as vectors at each vertex.
`void`	`showNone()` Clear all internal vector fields of this class and of the registered surface.
`void`	`start()` Start energy minimization in separate thread.
`void`	`step()` Move vertices in negative gradient direction a certain amount.
`void`	`step(int numSteps)` Move vertices in negative gradient direction a certain amount.
`void`	`stop()` Stop energy minimization in separate thread.
`boolean`	`update(java.lang.Object event)` Update the class whenever a child has changed.

Methods inherited from class jv.object.PsObject
addInspector, addUpdateListener, assureInspector, clearTag, clone, clone, clone, copy, getFather, getInfoPanel, getInspector, getName, getNumObjects, getSymbol, hasInspector, hasTag, hasUpdateListener, instanceOf, instanceOf, newInspector, newInspector, removeInspector, removeInspector, removeUpdateListener, setName, setParent, setSymbol, setTag, toString, updatePanels

Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Field Detail
  - DIRICHLET
```
public static final int DIRICHLET
```
    See Also:
    Constant Field Values
  - AREA
```
public static final int AREA
```
    See Also:
    Constant Field Values
  - CONFORMAL
```
public static final int CONFORMAL
```
    See Also:
    Constant Field Values
  - SPRING
```
public static final int SPRING
```
    See Also:
    Constant Field Values
  - ALIGNMENT
```
public static final int ALIGNMENT
```
    See Also:
    Constant Field Values
  - VOLUME
```
public static final int VOLUME
```
    See Also:
    Constant Field Values
  - GAUSS
```
public static final int GAUSS
```
    See Also:
    Constant Field Values
- Constructor Detail
  - PnEnergyMinimizer
```
public PnEnergyMinimizer()
```
- Method Detail
  - init
```
public void init()
```
    Description copied from class: PsObject
    
    If instance has missing name then assign default name 'Object_NUMBER' where number is the total number of already created instances.
    
    Overrides:
    
    init in class PsObject
  - update
```
public boolean update(java.lang.Object event)
```
    Update the class whenever a child has changed. Method is usually invoked from the children.
    
    Specified by:
    
    update in interface PsUpdateIf
    
    Overrides:
    
    update in class PsObject
    
    Parameters:
    event - carries a lot of information
    
    Returns:
    true if event has been handled, otherwise false
    See Also:
    PsObject.setParent(PsUpdateIf), PsObject.getFather(), PsObject.addUpdateListener(PsUpdateIf)
  - getEnergy
```
public PnEnergy getEnergy()
```
    Get current energy.
  - setEnergy
```
public void setEnergy(PnEnergy energy)
```
    Set new energy and clear all vector fields. Domain argument maybe null.
  - isEnabledFixVertices
```
public boolean isEnabledFixVertices()
```
    Determine if marked vertices remain fixed during minimization.
  - setEnabledFixVertices
```
public void setEnabledFixVertices(boolean flag)
```
    Enable if marked vertices remain fixed during minimization.
  - isEnabledConstrainMatrix
```
public boolean isEnabledConstrainMatrix()
```
    Determine if usage of a constrain matrix is enabled.
  - setEnabledConstrainMatrix
```
public void setEnabledConstrainMatrix(boolean flag)
```
    Enable usage of a constrain matrix for index computation of Neumann boundary geometries.
  - enableUpdateDomain
```
public void enableUpdateDomain(boolean flag)
```
    Flag whether domain is updated after each CG-minimization loop. When iteratively computing harmonic maps copy image surface into domain after minimization to update domain metric. Main use is inside Pinkall/Polthier algorithm on computing minimal surfaces by iterating harmonic maps.
  - getDomain
```
public PgElementSet getDomain()
```
    Get currently registered domain geometry.
  - getSurface
```
public PgElementSet getSurface()
```
    Get currently registered surface.
  - setSurface
```
public boolean setSurface(PgElementSet domain,
                 PgElementSet surface)
```
    Set references to domain and image surface. Image surface is usually being minimized while domain surface is often used when minimizing energy of maps between surfaces. Dimension of vertices of domain and surface may be different, e.g., domain may have 2-dimensional and surface may have 1-dimensional vertices.
    Remark: If the geometries are changed outside this energy minimizer, the user must call setSurface() again to update the energy minimizer. Otherwise, further minimization calls will use the old geometry information.
  - setNumLoops
```
public void setNumLoops(int numLoops)
```
    Set number of calls of conjugate gradient method to be performed during each call to PnEnergyMinimizer#minimize().
    This number of loops is independent of the number of iterations used in each single invocation of the CG-method, which depends on the requested accuracy PnEnergyMinimizer#m_cgEps.
    
    See Also:
    minimize()
  - minimize
```
public double minimize()
```
    Minimize energy by invoking conjugate gradient method in a loop. A separate thread is started which calls in each step a conjugate gradient method. The number of loops may be set using #setNumLoops(int).
    
    See Also:
    setNumLoops(int)
  - setUpdateDomain
```
public void setUpdateDomain(boolean flag)
```
    Set flag which enables the updating of the domain with the current surface after every minimization step. This is an essential part of the computation of minimal surface through an iteration of minimizing the Dirichlet energy, but in some other cases the domain is preferably not updated.
  - getInitialStepsize
```
public double getInitialStepsize()
```
    Get stepsize used in cg iteration.
  - setInitialStepsize
```
public void setInitialStepsize(double h)
```
    Set stepsize used in cg iteration.
  - step
```
public void step()
```
    Move vertices in negative gradient direction a certain amount. Amount is gradient*h with user defined stepsize. This method is applied numLoops times.
    
    See Also:
    step(int)
  - step
```
public void step(int numSteps)
```
    Move vertices in negative gradient direction a certain amount. Amount is gradient*h with h=0.01. This method is applied numSteps times.
    Method starts a new thread if numSteps>1 which calls step().
    
    See Also:
    step()
  - printGradient
```
public void printGradient()
```
    Evaluate and print the energy gradient to the JavaView console.
  - showNone
```
public void showNone()
```
    Clear all internal vector fields of this class and of the registered surface.
  - showGradient
```
public void showGradient()
```
    Evaluate and show the gradient as vectors at each vertex. This method assigns a new vector field to the surface, or reuses a vector field with name "Vector Field".
  - printHessian
```
public void printHessian()
```
    Evaluate the Hessian matrix of the energy and print its content to the JavaView console. This method should only be applied to surfaces with few coordinates.
  - computeEigenvectors
```
public int computeEigenvectors()
```
    Compute eigenvectors either of Hessian or of an L2-corrected Hessian.
  - printEigenvalues
```
public void printEigenvalues()
```
    Print eigenvalues of hessian to JavaView console. If the eigenvectors are null, then compute eigenvectors.
  - printEigenvectors
```
public void printEigenvectors()
```
    Print eigenvectors of hessian to JavaView console. If the eigenvectors are null, then compute eigenvectors.
  - saveEigenvectors
```
public void saveEigenvectors()
```
    Save eigenvectors of hessian as vector fields of the surface. If the eigenvectors are null, then compute eigenvectors.
  - showEigenvector
```
public void showEigenvector(int ind)
```
    Show eigenvectors of hessian as vector field on the surface. If the eigenvectors are null, then compute eigenvectors.
  - getEigenSolver
```
public java.lang.String[] getEigenSolver()
```
    Returns:
    Names of available eigensolver.
  - getEigenSolverPanel
```
public PsPanel getEigenSolverPanel(int id)
```
    Parameters:
    id - of eigensolver corresponding to order in of Names in Array returned by getEigenSolver().
    
    Returns:
    InfoPanel of eigensolver.
  - setEigenSolver
```
public void setEigenSolver(int id)
```
    Parameters:
    id - of eigensolver corresponding to order in of Names in Array returned by getEigenSolver().
  - isRunning
```
public boolean isRunning()
```
    Check whether energy minimizer will be stopped.
    
    Returns:
    false, if the energy minimizer will stop (just shutting down regularly).
  - isStopped
```
public boolean isStopped()
```
    Check whether energy minimizer is currently NOT running a minimizing thread.
  - start
```
public void start()
```
    Start energy minimization in separate thread.
  - stop
```
public void stop()
```
    Stop energy minimization in separate thread.
  - run
```
public void run()
```
    Do energy minimization until m_numLoops are done or until a call of stop().
    
    Specified by:
    
    run in interface java.lang.Runnable

Class PnEnergyMinimizer

Field Summary

Fields inherited from class jv.object.PsObject

Constructor Summary

Method Summary

Methods inherited from class jv.object.PsObject

Methods inherited from class java.lang.Object

Field Detail

DIRICHLET

AREA

CONFORMAL

SPRING

ALIGNMENT

VOLUME

GAUSS

Constructor Detail

PnEnergyMinimizer

Method Detail

init

update

getEnergy

setEnergy

isEnabledFixVertices

setEnabledFixVertices

isEnabledConstrainMatrix

setEnabledConstrainMatrix

enableUpdateDomain

getDomain

getSurface

setSurface

setNumLoops

minimize

setUpdateDomain

getInitialStepsize

setInitialStepsize

step

step

printGradient

showNone

showGradient

printHessian

computeEigenvectors

printEigenvalues

printEigenvectors

saveEigenvectors

showEigenvector

getEigenSolver

getEigenSolverPanel

setEigenSolver

isRunning

isStopped

start

stop

run