agi.foundation.geometry

(agi.foundation.core-2024r3.jar)

Class ConstantCovariance3By3

java.lang.Object

agi.foundation.infrastructure.DefinitionalObject

agi.foundation.geometry.DynamicCovariance3By3

agi.foundation.geometry.ConstantCovariance3By3

All Implemented Interfaces:

ICloneWithContext, IEnumerateDependencies, IEquatableDefinition, IFreezable, IServiceProvider

public class ConstantCovariance3By3
extends DynamicCovariance3By3

Represents position covariance with standard deviations which remain constant in the given axes.

Constructor Summary

Constructors

Modifier	Constructor and Description
	ConstantCovariance3By3() Initializes a new instance.
	ConstantCovariance3By3(Cartesian standardDeviations, Axes orientationAxes) Creates a new instance from the specified constant size and the orientation axes.
protected	ConstantCovariance3By3(ConstantCovariance3By3 existingInstance, CopyContext context) Initializes a new instance as a copy of an existing instance.

Method Summary

Modifier and Type	Method and Description
protected boolean	checkForSameDefinition(ConstantCovariance3By3 other) Checks to determine if another instance has the same definition as this instance and returns true if it does.
protected boolean	checkForSameDefinition(DynamicCovariance3By3 other) Checks to determine if another instance has the same definition as this instance and returns true if it does.
Object	clone(CopyContext context) Clones this object using the specified context.
protected int	computeCurrentDefinitionHashCode() Computes a hash code based on the current properties of this object.
void	enumerateDependencies(DependencyEnumerator enumerator) Enumerates the dependencies of this object by calling DependencyEnumerator#enumerate(T) for each object that this object directly depends upon.
Covariance3By3Evaluator	getEvaluator(Axes definedIn, EvaluatorGroup group) Constructs an evaluator that calculates the size and orientation of the position covariance over time.
Covariance3By3Evaluator	getEvaluator(EvaluatorGroup group) Constructs an evaluator that calculates the size and orientation of the position covariance over time.
Axes	getOrientationAxes() Gets the time-varying axes of the covariance ellipsoid.
Cartesian	getSigmas() Gets the Cartesian representing the constant Sigmas (get) for the location point uncertainty described by this instance.
void	setOrientationAxes(Axes orientationAxes) Sets the OrientationAxes (get).
void	setSigmas(Cartesian value) Sets the Cartesian representing the constant Sigmas (get) for the location point uncertainty described by this instance.

Methods inherited from class agi.foundation.geometry.DynamicCovariance3By3

checkForSameDefinition, getEllipsoidSizeEvaluator, getEllipsoidSizeEvaluator, getEvaluator, getEvaluator, getService, getStandardDeviationEvaluator, getStandardDeviationEvaluator

Methods inherited from class agi.foundation.infrastructure.DefinitionalObject

areSameDefinition, areSameDefinition, areSameDefinition, areSameDefinition, areSameDefinition, collectionItemsAreSameDefinition, collectionItemsAreSameDefinition, collectionItemsAreSameDefinition, dictionaryItemsAreSameDefinition, freeze, freezeAggregatedObjects, getCollectionHashCode, getCollectionHashCode, getCollectionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDictionaryHashCode, getIsFrozen, isSameDefinition, throwIfFrozen

Methods inherited from class java.lang.Object

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

Constructor Detail

ConstantCovariance3By3

public ConstantCovariance3By3()

Initializes a new instance. The user must set OrientationAxes (get) with ConstantCovariance3By3.setOrientationAxes(agi.foundation.geometry.Axes). Sigmas (get / set) is initialized to Zero (get).

ConstantCovariance3By3

public ConstantCovariance3By3(@Nonnull
                              Cartesian standardDeviations,
                              Axes orientationAxes)

Creates a new instance from the specified constant size and the orientation axes.

Parameters:

standardDeviations - The standard deviation, or sigmas, of the covariance ellipsoid axes.

orientationAxes - The orientation axes of the body axes of the covariance ellipsoid.

ConstantCovariance3By3

protected ConstantCovariance3By3(@Nonnull
                                 ConstantCovariance3By3 existingInstance,
                                 @Nonnull
                                 CopyContext context)

Initializes a new instance as a copy of an existing instance.

See ICloneWithContext.clone(CopyContext) for more information about how to implement this constructor in a derived class.

Parameters:

existingInstance - The existing instance to copy.

context - A CopyContext that controls the depth of the copy.

Throws:

ArgumentNullException - Thrown when existingInstance or context is null.

Method Detail

clone

public Object clone(CopyContext context)

Clones this object using the specified context.

This method should be implemented to call a copy constructor on the class of the object being cloned. The copy constructor should take the CopyContext as a parameter in addition to the existing instance to copy. The copy constructor should first call CopyContext.addObjectMapping(T, T) to identify the newly constructed instance as a copy of the existing instance. It should then copy all fields, using CopyContext.updateReference(T) to copy any reference fields.

A typical implementation of ICloneWithContext:

public static class MyClass implements ICloneWithContext {
    public MyClass(MyClass existingInstance, CopyContext context) {
        context.addObjectMapping(existingInstance, this);
        someReference = context.updateReference(existingInstance.someReference);
    }

    @Override
    public final Object clone(CopyContext context) {
        return new MyClass(this, context);
    }

    private Object someReference;
}

In general, all fields that are reference types should be copied with a call to CopyContext.updateReference(T). There are a couple of exceptions:

1. Fields that are aggregate parts of the object should always be copied. A referenced object is an aggregate if properties or methods on the object being copied can modify the externally-visible value of the referenced object.
2. If the semantics of the referenced object require that it have a single parent, owner, context, etc., and the object being copied is that parent, owner, or context, then the referenced object should always be copied.

If one of these exceptions applies, the CopyContext should be given an opportunity to update the reference before the reference is copied explicitly. Use CopyContext.updateReference(T) to update the reference. If CopyContext.updateReference(T) returns the original object, indicating that the context does not have a replacement registered, then copy the object manually by invoking a Clone method, a copy constructor, or by manually constructing a new instance and copying the values.

alwaysCopy = context.updateReference(existingInstance.alwaysCopy);
if (existingInstance.alwaysCopy != null && alwaysCopy == existingInstance.alwaysCopy) {
    alwaysCopy = (AlwaysCopy) existingInstance.alwaysCopy.clone(context);
}

If you are implementing an evaluator (a class that implements IEvaluator), the IEvaluator.updateEvaluatorReferences(agi.foundation.infrastructure.CopyContext) method shares some responsibilities with the copy context constructor. Code duplication can be avoided by doing the following:

1. For references to other evaluators ONLY, simply assign the reference in the constructor instead of calling CopyContext.updateReference(T). You should still call CopyContext.updateReference(T) on any references to non-evaluators.
2. Call IEvaluator.updateEvaluatorReferences(agi.foundation.infrastructure.CopyContext) as the last line in the constructor and pass it the same CopyContext passed to the constructor.
3. Implement IEvaluator.updateEvaluatorReferences(agi.foundation.infrastructure.CopyContext) as normal. See the reference documentation for IEvaluator.updateEvaluatorReferences(agi.foundation.infrastructure.CopyContext) for more information on implementing that method.

public MyClass(MyClass existingInstance, CopyContext context) {
    super(existingInstance, context);
    someReference = context.updateReference(existingInstance.someReference);
    evaluatorReference = existingInstance.evaluatorReference;
    updateEvaluatorReferences(context);
}

@Override
public void updateEvaluatorReferences(CopyContext context) {
    evaluatorReference = context.updateReference(evaluatorReference);
}

@Override
public Object clone(CopyContext context) {
    return new MyClass(this, context);
}

private Object someReference;
private IEvaluator evaluatorReference;

Specified by:

clone in interface ICloneWithContext

Specified by:

clone in class DefinitionalObject

Parameters:

context - The context to use to perform the copy.

Returns:

A new instance which is a copy of this object.

checkForSameDefinition

protected final boolean checkForSameDefinition(DynamicCovariance3By3 other)

Checks to determine if another instance has the same definition as this instance and returns true if it does. Derived classes MUST override this method and check all new fields introduced by the derived class for definitional equivalence. It is NOT necessary to check base class fields because the base class will already have done that. When overriding this method, you should NOT call the base implementation because it will return false for all derived-class instances. Derived classes should check the type of other to preserve the symmetric nature of IEquatableDefinition.isSameDefinition(java.lang.Object).

Specified by:

checkForSameDefinition in class DynamicCovariance3By3

Parameters:

other - The other instance to compare to this one.

Returns:

true if the two objects are defined equivalently; otherwise false.

checkForSameDefinition

protected boolean checkForSameDefinition(ConstantCovariance3By3 other)

Checks to determine if another instance has the same definition as this instance and returns true if it does. Derived classes MUST override this method and check all new fields introduced by the derived class for definitional equivalence. It is NOT necessary to check base class fields because the base class will already have done that. When overriding this method, you should NOT call the base implementation because it will return false for all derived-class instances. Derived classes should check the type of other to preserve the symmetric nature of IEquatableDefinition.isSameDefinition(java.lang.Object).

Parameters:

other - The other instance to compare to this one.

Returns:

true if the two objects are defined equivalently; otherwise false.

computeCurrentDefinitionHashCode

protected int computeCurrentDefinitionHashCode()

Computes a hash code based on the current properties of this object. Derived classes MUST override this method and compute a hash code that combines: a unique hash code seed, the base implementation result, and the hash codes of all new fields introduced by the derived class which are used in the ConstantCovariance3By3.checkForSameDefinition(agi.foundation.geometry.DynamicCovariance3By3) method.

Overrides:

computeCurrentDefinitionHashCode in class DynamicCovariance3By3

Returns:

The computed hash code.

enumerateDependencies

public void enumerateDependencies(DependencyEnumerator enumerator)

Enumerates the dependencies of this object by calling DependencyEnumerator#enumerate(T) for each object that this object directly depends upon. Derived classes which contain additional dependencies MUST override this method, call the base implementation, and enumerate dependencies introduced by the derived class.

Specified by:

enumerateDependencies in interface IEnumerateDependencies

Overrides:

enumerateDependencies in class DefinitionalObject

Parameters:

enumerator - The enumerator that is informed of the dependencies of this object.

getEvaluator

public Covariance3By3Evaluator getEvaluator(EvaluatorGroup group)

Constructs an evaluator that calculates the size and orientation of the position covariance over time.

Specified by:

getEvaluator in class DynamicCovariance3By3

Parameters:

group - The evaluator group in which to create the evaluator.

Returns:

The covariance evaluator.

getEvaluator

public Covariance3By3Evaluator getEvaluator(Axes definedIn,
                                            EvaluatorGroup group)

Constructs an evaluator that calculates the size and orientation of the position covariance over time.

Specified by:

getEvaluator in class DynamicCovariance3By3

Parameters:

definedIn - The reference axes the results will be defined in. The evaluated Covariance3By3SizeAndOrientation's Rotation (get) property is the rotation from the OrientationAxes (get) to this axes.

group - The evaluator group in which to create the evaluator.

Returns:

The covariance evaluator.

getOrientationAxes

public Axes getOrientationAxes()

Gets the time-varying axes of the covariance ellipsoid. This property can be set with ConstantCovariance3By3.setOrientationAxes(agi.foundation.geometry.Axes).

Specified by:

getOrientationAxes in class DynamicCovariance3By3

getSigmas

@Nonnull
public final Cartesian getSigmas()

Gets the Cartesian representing the constant Sigmas (get) for the location point uncertainty described by this instance. These are equal to the square root of the standard deviation of the covariances, and are the semi-axes lengths of the covariance ellipsoid at one standard deviation of uncertainty.

setSigmas

public final void setSigmas(@Nonnull
                            Cartesian value)

Sets the Cartesian representing the constant Sigmas (get) for the location point uncertainty described by this instance. These are equal to the square root of the standard deviation of the covariances, and are the semi-axes lengths of the covariance ellipsoid at one standard deviation of uncertainty.

setOrientationAxes

public final void setOrientationAxes(Axes orientationAxes)

Sets the OrientationAxes (get).

Parameters:

orientationAxes - The orientation axes of the body axes of the covariance ellipsoid.