fr.cnes.sirius.patrius.events.utils

Class OneSatEventDetectorWrapper

java.lang.Object

fr.cnes.sirius.patrius.events.MultiAbstractDetector

fr.cnes.sirius.patrius.events.utils.OneSatEventDetectorWrapper

All Implemented Interfaces:

MultiEventDetector

public class OneSatEventDetectorWrapper
extends MultiAbstractDetector

This class allows to convert an EventDetector into a MultiEventDetector. The EventDetector is associated with a single spacecraft identified by its ID.

Since:

3.0

Version:

$Id$

Author:

maggioranic

See Also:

MultiPropagator.addEventDetector(EventDetector, String)

Concurrency :

not thread-safe

Field Summary

Fields inherited from class fr.cnes.sirius.patrius.events.MultiAbstractDetector

DEFAULT_MAX_ITERATION_COUNT, DEFAULT_MAXCHECK, DEFAULT_THRESHOLD

Fields inherited from interface fr.cnes.sirius.patrius.events.MultiEventDetector

DECREASING, INCREASING, INCREASING_DECREASING

Constructor Summary

Constructors

Constructor and Description
OneSatEventDetectorWrapper(EventDetector detector, String satId) Simple constructor.

Method Summary

Modifier and Type	Method and Description
EventDetector.Action	eventOccurred(Map<String,SpacecraftState> state, boolean increasing, boolean forward) Handle an event and choose what to do next.
boolean	filterEvent(Map<String,SpacecraftState> states, boolean increasing, boolean forward) Filter last event: returns true if the last event is a false detection, false otherwise.
double	g(Map<String,SpacecraftState> state) Compute the value of the switching function.
double	g(SpacecraftState state) Compute the value of the switching function.
String	getID() Returns the ID of the spacecraft associated with the detector.
void	init(Map<String,SpacecraftState> statesMap, AbsoluteDate date) Initialize event handler at the start of a propagation.
Map<String,SpacecraftState>	resetStates(Map<String,SpacecraftState> oldStates) Reset the states (including additional states) prior to continue propagation.
boolean	shouldBeRemoved() This method is called after the step handler has returned and before the next step is started, but only when MultiEventDetector.eventOccurred(java.util.Map<java.lang.String, fr.cnes.sirius.patrius.propagation.SpacecraftState>, boolean, boolean) has been called.

Methods inherited from class fr.cnes.sirius.patrius.events.MultiAbstractDetector

getMaxCheckInterval, getMaxIterationCount, getSlopeSelection, getThreshold

Methods inherited from class java.lang.Object

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

Constructor Detail

OneSatEventDetectorWrapper

public OneSatEventDetectorWrapper(EventDetector detector,
                                  String satId)

Simple constructor.

Parameters:

detector - the event detector

satId - the ID of the spacecraft associated with the detector

Method Detail

init

public void init(Map<String,SpacecraftState> statesMap,
                 AbsoluteDate date)
          throws PatriusException

Initialize event handler at the start of a propagation.

This method is called once at the start of the propagation. It may be used by the event handler to initialize some internal data if needed.

Specified by:

init in interface MultiEventDetector

Overrides:

init in class MultiAbstractDetector

Parameters:

statesMap - map of initial states

date - target time for the integration

Throws:

PatriusException - thrown if initialization failed

g

public double g(SpacecraftState state)
         throws PatriusException

Compute the value of the switching function. This function is not meant to be used by external user. Hence its visibility has been limited to package.

Parameters:

state - the current states information: date, kinematics, attitudes for forces and events computation, and additional states for each states

Returns:

value of the switching function

Throws:

PatriusException - if some specific error occurs

g

public double g(Map<String,SpacecraftState> state)
         throws PatriusException

Compute the value of the switching function.

This function must be continuous (at least in its roots neighborhood), as the integrator will need to find its roots to locate the events.

Specified by:

g in interface MultiEventDetector

Specified by:

g in class MultiAbstractDetector

Parameters:

state - the current states information: date, kinematics, attitudes for forces and events computation, and additional states for each states

Returns:

value of the switching function

Throws:

PatriusException - if some specific error occurs

eventOccurred

public EventDetector.Action eventOccurred(Map<String,SpacecraftState> state,
                                          boolean increasing,
                                          boolean forward)
                                   throws PatriusException

Handle an event and choose what to do next.

The scheduling between this method and the MultiOrekitStepHandler method handleStep is to call this method first and handleStep afterwards. This scheduling allows the propagator to pass true as the isLast parameter to the step handler to make it aware the step will be the last one if this method returns EventDetector.Action.STOP. As the interpolator may be used to navigate back throughout the last step MultiOrekitStepNormalizer does for example), user code called by this method and user code called by step handlers may experience apparently out of order values of the independent time variable. As an example, if the same user object implements both this MultiEventDetector interface and the MultiOrekitFixedStepHandler interface, a forward integration may call its eventOccurred method with a state at 2000-01-01T00:00:10 first and call its handleStep method with a state at 2000-01-01T00:00:09 afterwards. Such out of order calls are limited to the size of the integration step for MultiOrekitStepHandler and to the size of the fixed step for MultiOrekitFixedStepHandler.

Specified by:

eventOccurred in interface MultiEventDetector

Specified by:

eventOccurred in class MultiAbstractDetector

Parameters:

state - the current states information: date, kinematics, attitude for forces and events computation, and additional states for each states

increasing - if true, the value of the switching function increases when times increases around event (note that increase is measured with respect to physical time, not with respect to propagation which may go backward in time)

forward - if true, the integration variable (time) increases during integration.

Returns:

one of EventDetector.Action.STOP, EventDetector.Action.RESET_STATE, EventDetector.Action.RESET_DERIVATIVES, EventDetector.Action.CONTINUE

Throws:

PatriusException - if some specific error occurs

shouldBeRemoved

public boolean shouldBeRemoved()

This method is called after the step handler has returned and before the next step is started, but only when MultiEventDetector.eventOccurred(java.util.Map<java.lang.String, fr.cnes.sirius.patrius.propagation.SpacecraftState>, boolean, boolean) has been called.

Specified by:

shouldBeRemoved in interface MultiEventDetector

Specified by:

shouldBeRemoved in class MultiAbstractDetector

Returns:

true if the current detector should be removed

resetStates

public Map<String,SpacecraftState> resetStates(Map<String,SpacecraftState> oldStates)
                                        throws PatriusException

Reset the states (including additional states) prior to continue propagation.

This method is called after the step handler has returned and before the next step is started, but only when MultiEventDetector.eventOccurred(java.util.Map<java.lang.String, fr.cnes.sirius.patrius.propagation.SpacecraftState>, boolean, boolean) has itself returned the EventDetector.Action.RESET_STATE indicator. It allows the user to reset the state for the next step, without perturbing the step handler of the finishing step. If the MultiEventDetector.eventOccurred(java.util.Map<java.lang.String, fr.cnes.sirius.patrius.propagation.SpacecraftState>, boolean, boolean) never returns the EventDetector.Action.RESET_STATE indicator, this function will never be called, and it is safe to simply return null.

Specified by:

resetStates in interface MultiEventDetector

Overrides:

resetStates in class MultiAbstractDetector

Parameters:

oldStates - old states

Returns:

new states

Throws:

PatriusException - if the states cannot be reseted

filterEvent

public boolean filterEvent(Map<String,SpacecraftState> states,
                           boolean increasing,
                           boolean forward)
                    throws PatriusException

Filter last event: returns true if the last event is a false detection, false otherwise.

This method is called right before MultiEventDetector.eventOccurred(Map, boolean, boolean) method.

This may be useful in order to filter some events in particular when angles are at stake (see for example LocalTimeAngleDetector).

Specified by:

filterEvent in interface MultiEventDetector

Overrides:

filterEvent in class MultiAbstractDetector

Parameters:

states - states at last event occurrence

increasing - if true, the value of the switching function increases when times increases around event (note that increase is measured with respect to physical time, not with respect to propagation which may go backward in time)

forward - if true, the integration variable (time) increases during integration.

Returns:

true if the last event is a false detection, false otherwise

Throws:

PatriusException - thrown if computation failed for some reasons

getID

public String getID()

Returns the ID of the spacecraft associated with the detector.

Returns:

the ID of the spacecraft associated with the detector