jvx.numeric

Class PnGeodesicRK

java.lang.Object

jv.object.PsObject

jvx.numeric.PnGeodesicRK

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable, PsUpdateIf

Direct Known Subclasses:

PnElementRK, PnTranslationRK, PnVertexRK, PnVertexRKIgnoreDirection

public abstract class PnGeodesicRK
extends PsObject

Discrete Runge-Kutta solver on triangular element sets. Element set must be triangulated.

See Also:

PnElementRK, PnVertexRK, PnVertexRKIgnoreDirection, PgElementSet.triangulate(jv.geom.PgElementSet), Serialized Form

Author:

Eike Preuß

Version:

01.03.06, 1.40 revised (ah) Use PnStraightestGeodesic.
20.02.03, 1.30 revised (ep) New method eval that returns the evaluation result in new allocated baryvector.
22.01.03, 1.20 revised (ep) You can invert the direction of integration with get/setInvertDirection.
15.01.03, 1.10 revised (ep) Changes with respect to new RK class that ignores the sign (direction) of vector fields.
11.07.01, 1.05 revised (ep) Speed optimization in the whole thing.
20.02.00, 1.04 revised (ep) removed "small velocity bug", added StepLength 28.12.99, 1.03 revised (ep) added fast-mode (euler-mode)
27.12.99, 1.02 revised (ep) corrected handling of |vector| == 0
21.11.99, 1.01 revised (ep) split into PnGeodesicRK, PnVertexRK, PnElementRK

Field Summary

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
PnGeodesicRK(PgElementSet geom)

Method Summary

Modifier and Type	Method and Description
PdBaryDir	eval(int elemInd, PdBary bary) Wrapper that calls eval(int, PdBary, PdBaryDir) with a new barycentric vector.
abstract void	eval(int elemInd, PdBary bary, PdBaryDir out) Evaluate vector field on given element at given barycentric coordinate.
boolean	getInvertDirection()
double	getStepLength() Returns Euclidean length of last Runge-Kutta step.
boolean	nextStep() Calculates the next step of actual integration.
boolean	prepareSolve(PgPolygonOnElementSet outpoly, int iniElem, PdBary iniPoint, double h) Unless solve is used, this method has to be called before integration.
void	setFirstOrder(boolean flag) Sets integration method to euler if flag is true, else to 4th-order Runge-Kutta.
void	setFourthOrder(boolean flag) Sets integration method to 4th-order Runge-Kutta if flag is true, else to euler.
void	setGeometry(PgElementSet geom) Sets underlying geometry.
void	setInvertDirection(boolean flag) If set to 'true', the negative vector field is used.
void	solve(PdBary initPoint, double h, int numIterations, PdBary outPoint) Solves for outPoint at initPoint.
void	solve(PdBary initPoint, double h, PdBary outPoint) Solves for outPoint at initPoint.
void	solve(PgPolygonOnElementSet outpoly, int iniElem, PdBary iniPoint, double h, int numIterations) Returns a whole integral line.

Methods inherited from class jv.object.PsObject

addInspector, addUpdateListener, assureInspector, clearTag, clone, clone, clone, copy, getFather, getInfoPanel, getInspector, getName, getNumObjects, getSymbol, hasInspector, hasTag, hasUpdateListener, init, instanceOf, instanceOf, newInspector, newInspector, removeInspector, removeInspector, removeUpdateListener, setName, setParent, setSymbol, setTag, toString, update, updatePanels

Methods inherited from class java.lang.Object

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

Constructor Detail

PnGeodesicRK

public PnGeodesicRK(PgElementSet geom)

Method Detail

setGeometry

public void setGeometry(PgElementSet geom)

Sets underlying geometry.

Parameters:

geom - new underlying geometry

setFirstOrder

public void setFirstOrder(boolean flag)

Sets integration method to euler if flag is true, else to 4th-order Runge-Kutta.

Parameters:

flag - true: euler; false: 4th-order RK

setFourthOrder

public void setFourthOrder(boolean flag)

Sets integration method to 4th-order Runge-Kutta if flag is true, else to euler.

Parameters:

flag - true: 4th-order RK; false: euler

solve

public void solve(PgPolygonOnElementSet outpoly,
                  int iniElem,
                  PdBary iniPoint,
                  double h,
                  int numIterations)

Returns a whole integral line. To get an integral line of unfixed length step by step, use prepareSolve, nextStep and getStepPolygon.

Parameters:

outpoly - output polygon

iniElem - initial element index

iniPoint - initial barycentric coordinates

h - stepsize

numIterations - number of iterations

See Also:

prepareSolve(jvx.geom.PgPolygonOnElementSet, int, jv.vecmath.PdBary, double), nextStep(), getStepLength()

solve

public void solve(PdBary initPoint,
                  double h,
                  int numIterations,
                  PdBary outPoint)

Solves for outPoint at initPoint.

Parameters:

initPoint - input

h - stepsize

numIterations - number of iterations

outPoint - output

Version:

01.03.06, 1.00 created (ah)

solve

public void solve(PdBary initPoint,
                  double h,
                  PdBary outPoint)

Solves for outPoint at initPoint.

Parameters:

initPoint - input

h - stepsize

outPoint - output

Version:

01.03.06, 1.00 created (ah)

prepareSolve

public boolean prepareSolve(PgPolygonOnElementSet outpoly,
                            int iniElem,
                            PdBary iniPoint,
                            double h)

Unless solve is used, this method has to be called before integration. It initializes all internal variables.

Parameters:

outpoly - output polygon

iniElem - initial element index

iniPoint - initial barycentric coordinates

h - stepsize

See Also:

solve(PdBary, double, int, PdBary)

nextStep

public boolean nextStep()

Calculates the next step of actual integration.

Returns:

false if the integration stopped by error, the geometry boundary was reached, or the next direction would be of zero length

See Also:

solve(PdBary, double, int, PdBary), prepareSolve(jvx.geom.PgPolygonOnElementSet, int, jv.vecmath.PdBary, double), getStepLength()

Version:

01.03.06, 1.20 revised (ah) Avoid unnecessary copying
. 01.03.06, 1.10 revised (ah) Use PnStraightestGeodesic

getStepLength

public double getStepLength()

Returns Euclidean length of last Runge-Kutta step.

setInvertDirection

public void setInvertDirection(boolean flag)

If set to 'true', the negative vector field is used. MUST BE SUPPORTED BY EVAL-METHOD OF SUBCLASSES.

Since:

JavaView 2.49.004

getInvertDirection

public boolean getInvertDirection()

Since:

JavaView 2.49.004

eval

public abstract void eval(int elemInd,
                          PdBary bary,
                          PdBaryDir out)

Evaluate vector field on given element at given barycentric coordinate.

Parameters:

elemInd - the element in which the vector field will be evaluated

bary - barycentric coordinates of the point in which the vector field will be evaluated

out - output: in this PdBaryDir the evaluated direction will be stored

See Also:

PnElementRK.eval(int, jv.vecmath.PdBary, jv.vecmath.PdBaryDir), PnVertexRK.eval(int, jv.vecmath.PdBary, jv.vecmath.PdBaryDir), PnTranslationRK.eval(int, jv.vecmath.PdBary, jv.vecmath.PdBaryDir)

eval

public PdBaryDir eval(int elemInd,
                      PdBary bary)

Wrapper that calls eval(int, PdBary, PdBaryDir) with a new barycentric vector.

Since:

JavaView xx.xx.xxx