org.orekit.propagation.events

Class FunctionalDetector

java.lang.Object

org.orekit.propagation.events.AbstractDetector<FunctionalDetector>

org.orekit.propagation.events.FunctionalDetector

All Implemented Interfaces:

EventDetector

public class FunctionalDetector
extends AbstractDetector<FunctionalDetector>

A detector that implements the g(SpacecraftState) function using a lambda that can be set using withFunction(ToDoubleFunction).

For example, to create a simple date detector use:

 FunctionalDetector d = new FunctionalDetector()
     .withGFunction((s) -> s.getDate().durationFrom(triggerDate))
     .withMaxCheck(1e10);
 

Since:

9.2

Author:

Evan Ward

Field Summary

Fields inherited from class org.orekit.propagation.events.AbstractDetector

DEFAULT_MAX_ITER, DEFAULT_MAXCHECK, DEFAULT_THRESHOLD

Constructor Summary

Constructors

Modifier	Constructor and Description
	FunctionalDetector() Create an event detector with the default values.
protected	FunctionalDetector(AdaptableInterval maxCheck, double threshold, int maxIter, EventHandler handler, ToDoubleFunction<SpacecraftState> function) Private constructor.

Method Summary

Modifier and Type	Method and Description
protected FunctionalDetector	create(AdaptableInterval newMaxCheck, double newThreshold, int newMaxIter, EventHandler newHandler) Build a new instance.
double	g(SpacecraftState s) Compute the value of the switching function.
ToDoubleFunction<SpacecraftState>	getFunction() Get the switching function.
FunctionalDetector	withFunction(ToDoubleFunction<SpacecraftState> newGFunction) Create a new event detector with a new g function, keeping all other attributes the same.

Methods inherited from class org.orekit.propagation.events.AbstractDetector

getHandler, getMaxCheckInterval, getMaxIterationCount, getThreshold, init, isForward, withHandler, withMaxCheck, withMaxCheck, withMaxIter, withThreshold

Methods inherited from class java.lang.Object

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

Constructor Detail

FunctionalDetector

public FunctionalDetector()

Create an event detector with the default values. These are AbstractDetector.DEFAULT_MAXCHECK, AbstractDetector.DEFAULT_THRESHOLD, AbstractDetector.DEFAULT_MAX_ITER, ContinueOnEvent, and a g function that is identically unity.

FunctionalDetector

protected FunctionalDetector(AdaptableInterval maxCheck,
                             double threshold,
                             int maxIter,
                             EventHandler handler,
                             ToDoubleFunction<SpacecraftState> function)

Private constructor.

Parameters:

maxCheck - maximum checking interval

threshold - convergence threshold (s)

maxIter - maximum number of iterations in the event time search

handler - event handler to call at event occurrences

function - the switching function.

Method Detail

g

public double g(SpacecraftState s)

Description copied from class: AbstractDetector

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 EventDetector

Specified by:

g in class AbstractDetector<FunctionalDetector>

Parameters:

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

Returns:

value of the switching function

create

protected FunctionalDetector create(AdaptableInterval newMaxCheck,
                                    double newThreshold,
                                    int newMaxIter,
                                    EventHandler newHandler)

Description copied from class: AbstractDetector

Build a new instance.

Specified by:

create in class AbstractDetector<FunctionalDetector>

Parameters:

newMaxCheck - maximum checking interval (s)

newThreshold - convergence threshold (s)

newMaxIter - maximum number of iterations in the event time search

newHandler - event handler to call at event occurrences

Returns:

a new instance of the appropriate sub-type

withFunction

public FunctionalDetector withFunction(ToDoubleFunction<SpacecraftState> newGFunction)

Create a new event detector with a new g function, keeping all other attributes the same. It is recommended to use AbstractDetector.withMaxCheck(AdaptableInterval) and AbstractDetector.withThreshold(double) to set appropriate values for this g function.

Parameters:

newGFunction - the new g function.

Returns:

a new detector with the new g function.

getFunction

public ToDoubleFunction<SpacecraftState> getFunction()

Get the switching function.

Returns:

the function used in g(SpacecraftState).