fr.cnes.sirius.patrius.propagation.events

Class DateDetector

java.lang.Object

fr.cnes.sirius.patrius.propagation.events.AbstractDetector

fr.cnes.sirius.patrius.propagation.events.DateDetector

All Implemented Interfaces:

EventDetector, TimeStamped, Serializable

Direct Known Subclasses:

RelativeDateDetector

public class DateDetector
extends AbstractDetector
implements TimeStamped

Finder for date events.

This class finds date events (i.e. occurrence of some predefined dates).

As of version 5.1, it is an enhanced date detector:

• it can be defined without prior date (DateDetector(double,double))
• several dates can be added (addEventDate(AbsoluteDate))

The gap between the added dates must be more than the maxCheck.

The default implementation behavior is to stop propagation at the first event date occurrence. This can be changed by using provided constructors.

Author:

Luc Maisonobe, Pascal Parraud

See Also:

Propagator.addEventDetector(EventDetector), Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from interface fr.cnes.sirius.patrius.propagation.events.EventDetector

EventDetector.Action

Field Summary

Fields

Modifier and Type	Field and Description
static double	DEFAULT_MAXCHECK Default convergence threshold (s).
static double	DEFAULT_THRESHOLD Default convergence threshold (s).

Fields inherited from interface fr.cnes.sirius.patrius.propagation.events.EventDetector

DECREASING, INCREASING, INCREASING_DECREASING

Constructor Summary

Constructors

Constructor and Description
DateDetector(AbsoluteDate target) Build a new instance.
DateDetector(AbsoluteDate target, double maxCheck, double threshold) Build a new instance.
DateDetector(AbsoluteDate target, double maxCheck, double threshold, EventDetector.Action action) Build a new instance.
DateDetector(AbsoluteDate target, double maxCheck, double threshold, EventDetector.Action action, boolean remove) Build a new instance.
DateDetector(double maxCheck, double threshold) Build a new instance.
DateDetector(double maxCheck, double threshold, EventDetector.Action action) Build a new instance.
DateDetector(double maxCheck, double threshold, EventDetector.Action action, boolean remove) Build a new instance.

Method Summary

Modifier and Type	Method and Description
void	addEventDate(AbsoluteDate target) Add an event date.
EventDetector	copy() A copy of the detector.
EventDetector.Action	eventOccurred(SpacecraftState s, boolean increasing, boolean forward) Handle a date event and choose what to do next.
double	g(SpacecraftState s) Compute the value of the switching function.
EventDetector.Action	getAction() Return the action at detection.
AbsoluteDate	getDate() Get the current event date according to the propagator.
boolean	shouldBeRemoved() This method is called after EventDetector.eventOccurred(fr.cnes.sirius.patrius.propagation.SpacecraftState, boolean, boolean) has been triggered.

Methods inherited from class fr.cnes.sirius.patrius.propagation.events.AbstractDetector

getMaxCheckInterval, getMaxIterationCount, getSlopeSelection, getThreshold, init, resetState

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_THRESHOLD

public static final double DEFAULT_THRESHOLD

Default convergence threshold (s).

See Also:

Constant Field Values

DEFAULT_MAXCHECK

public static final double DEFAULT_MAXCHECK

Default convergence threshold (s).

See Also:

Constant Field Values

Constructor Detail

DateDetector

public DateDetector(double maxCheck,
                    double threshold)

Build a new instance.

This constructor is dedicated to date detection when the event date is not known before propagating. It can be triggered later by adding some event date, it then acts like a timer.

The default implementation behavior is to stop propagation at date occurrence.

Parameters:

maxCheck - maximum checking interval (s)

threshold - convergence threshold (s)

See Also:

addEventDate(AbsoluteDate)

DateDetector

public DateDetector(double maxCheck,
                    double threshold,
                    EventDetector.Action action)

Build a new instance.

This constructor is dedicated to date detection when the event date is not known before propagating. It can be triggered later by adding some event date, it then acts like a timer.

Parameters:

maxCheck - maximum checking interval (s)

threshold - convergence threshold (s)

action - action performed at date detection

See Also:

addEventDate(AbsoluteDate)

DateDetector

public DateDetector(double maxCheck,
                    double threshold,
                    EventDetector.Action action,
                    boolean remove)

Build a new instance.

This constructor is dedicated to date detection when the event date is not known before propagating. It can be triggered later by adding some event date, it then acts like a timer.

Parameters:

maxCheck - maximum checking interval (s)

threshold - convergence threshold (s)

action - action performed at date detection

remove - true if detector should be removed after first detection

See Also:

addEventDate(AbsoluteDate)

DateDetector

public DateDetector(AbsoluteDate target,
                    double maxCheck,
                    double threshold)

Build a new instance.

First event date is set here, but others can be added later with addEventDate(AbsoluteDate).

The default implementation behavior is to stop propagation at date occurrence.

Parameters:

target - target date

maxCheck - maximum checking interval (s)

threshold - convergence threshold (s)

See Also:

addEventDate(AbsoluteDate)

DateDetector

public DateDetector(AbsoluteDate target,
                    double maxCheck,
                    double threshold,
                    EventDetector.Action action)

Build a new instance.

First event date is set here, but others can be added later with addEventDate(AbsoluteDate).

Parameters:

target - target date

maxCheck - maximum checking interval (s)

threshold - convergence threshold (s)

action - action performed at date detection

See Also:

addEventDate(AbsoluteDate)

DateDetector

public DateDetector(AbsoluteDate target,
                    double maxCheck,
                    double threshold,
                    EventDetector.Action action,
                    boolean remove)

Build a new instance.

First event date is set here, but others can be added later with addEventDate(AbsoluteDate).

Parameters:

target - target date

maxCheck - maximum checking interval (s)

threshold - convergence threshold (s)

action - action performed at date detection

remove - true if detector should be removed after first detection

Since:

3.1

See Also:

addEventDate(AbsoluteDate)

DateDetector

public DateDetector(AbsoluteDate target)

Build a new instance.

This constructor is dedicated to single date detection. MaxCheck is set to 10.e9, so almost no other date can be added. Tolerance is set to 10.e-10.

Parameters:

target - target date

See Also:

addEventDate(AbsoluteDate)

Method Detail

eventOccurred

public EventDetector.Action eventOccurred(SpacecraftState s,
                                          boolean increasing,
                                          boolean forward)
                                   throws PatriusException

Handle a date event and choose what to do next.

Specified by:

eventOccurred in interface EventDetector

Specified by:

eventOccurred in class AbstractDetector

Parameters:

s - the current state information : date, kinematics, attitude

increasing - the way of the switching function is not guaranted as it can change according to the added event dates

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

Returns:

the action performed at the first event date occurrence.

Throws:

PatriusException - if some specific error occurs

shouldBeRemoved

public boolean shouldBeRemoved()

This method is called after EventDetector.eventOccurred(fr.cnes.sirius.patrius.propagation.SpacecraftState, boolean, boolean) has been triggered. It returns true if the current detector should be removed after first event detection. WARNING: this method can be called only once a event has been triggered. Before, the value is not available.

Specified by:

shouldBeRemoved in interface EventDetector

Specified by:

shouldBeRemoved in class AbstractDetector

Returns:

true if the current detector should be removed after first event detection

g

public double g(SpacecraftState s)
         throws PatriusException

Compute the value of the switching function. This function measures the difference between the current and the target date.

Specified by:

g in interface EventDetector

Specified by:

g in class AbstractDetector

Parameters:

s - the current state information: date, kinematics, attitude

Returns:

value of the switching function

Throws:

PatriusException - if some specific error occurs

getDate

public AbsoluteDate getDate()

Get the current event date according to the propagator.

Specified by:

getDate in interface TimeStamped

Returns:

event date

getAction

public EventDetector.Action getAction()

Return the action at detection.

Returns:

action at detection

addEventDate

public void addEventDate(AbsoluteDate target)

Add an event date.

The date to add must be:

• less than the smallest already registered event date minus the maxCheck
• or more than the largest already registered event date plus the maxCheck

Parameters:

target - target date

Throws:

IllegalArgumentException - if the date is too close from already defined interval

See Also:

DateDetector(double, double)

copy

public EventDetector copy()

A copy of the detector. By default copy is deep. If not, detector javadoc will specify which attribute is not fully copied. In that case, the attribute reference is passed.

Specified by:

copy in interface EventDetector

Returns:

a copy of the detector.