Package org.orekit.estimation.measurements.generation

Class AbstractMeasurementBuilder<T extends ObservedMeasurement<T>>

java.lang.Object

org.orekit.estimation.measurements.generation.AbstractMeasurementBuilder<T>

Type Parameters:

T - the type of the measurement

All Implemented Interfaces:

MeasurementBuilder<T>

Direct Known Subclasses:

AngularAzElBuilder, AngularRaDecBuilder, InterSatellitesRangeBuilder, PositionBuilder, PVBuilder, RangeBuilder, RangeRateBuilder, TurnAroundRangeBuilder

public abstract class AbstractMeasurementBuilder<T extends ObservedMeasurement<T>>
extends Object
implements MeasurementBuilder<T>

Base class for measurements builders.

Since:

9.3

Author:

Luc Maisonobe

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	AbstractMeasurementBuilder(org.hipparchus.random.CorrelatedRandomVectorGenerator noiseSource, double[] sigma, double[] baseWeight, ObservableSatellite... satellites)	Simple constructor.
protected	AbstractMeasurementBuilder(org.hipparchus.random.CorrelatedRandomVectorGenerator noiseSource, double sigma, double baseWeight, ObservableSatellite... satellites)	Simple constructor.

Method Summary

Modifier and Type	Method	Description
void	addModifier(EstimationModifier<T> modifier)	Add a modifier.
protected double[]	getBaseWeight()	Get the base weight associated with the measurement
protected AbsoluteDate	getEnd()	Get the end of the measurements time span.
List<EstimationModifier<T>>	getModifiers()	Get the modifiers that apply to a measurement.
protected double[]	getNoise()	Generate a noise vector.
protected ObservableSatellite[]	getSatellites()	Get the satellites related to this measurement.
protected AbsoluteDate	getStart()	Get the start of the measurements time span.
protected double[]	getTheoreticalStandardDeviation()	Get the theoretical standard deviation.
void	init(AbsoluteDate start, AbsoluteDate end)	Initialize builder at the start of a measurements generation.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.orekit.estimation.measurements.generation.MeasurementBuilder

build

Constructor Detail

AbstractMeasurementBuilder

protected AbstractMeasurementBuilder(org.hipparchus.random.CorrelatedRandomVectorGenerator noiseSource,
                                     double sigma,
                                     double baseWeight,
                                     ObservableSatellite... satellites)

Simple constructor.

Parameters:

noiseSource - noise source, may be null for generating perfect measurements

sigma - theoretical standard deviation

baseWeight - base weight

satellites - satellites related to this builder

AbstractMeasurementBuilder

protected AbstractMeasurementBuilder(org.hipparchus.random.CorrelatedRandomVectorGenerator noiseSource,
                                     double[] sigma,
                                     double[] baseWeight,
                                     ObservableSatellite... satellites)

Simple constructor.

Parameters:

noiseSource - noise source, may be null for generating perfect measurements

sigma - theoretical standard deviation

baseWeight - base weight

satellites - satellites related to this builder

Method Detail

init

public void init(AbsoluteDate start,
                 AbsoluteDate end)

Initialize builder at the start of a measurements generation.

This method is called once at the start of the measurements generation. It may be used by the builder to initialize some internal data if needed, typically setting up parameters reference dates.

This implementation stores the time span of the measurements generation.

Specified by:

init in interface MeasurementBuilder<T extends ObservedMeasurement<T>>

Parameters:

start - start of the measurements time span

end - end of the measurements time span

addModifier

public void addModifier(EstimationModifier<T> modifier)

Add a modifier.

Specified by:

addModifier in interface MeasurementBuilder<T extends ObservedMeasurement<T>>

Parameters:

modifier - modifier to add

getModifiers

public List<EstimationModifier<T>> getModifiers()

Get the modifiers that apply to a measurement.

Specified by:

getModifiers in interface MeasurementBuilder<T extends ObservedMeasurement<T>>

Returns:

modifiers that apply to a measurement

See Also:

MeasurementBuilder.addModifier(EstimationModifier)

getStart

protected AbsoluteDate getStart()

Get the start of the measurements time span.

Returns:

start of the measurements time span

getEnd

protected AbsoluteDate getEnd()

Get the end of the measurements time span.

Returns:

end of the measurements time span

getNoise

protected double[] getNoise()

Generate a noise vector.

Returns:

noise vector (null if we generate perfect measurements)

getTheoreticalStandardDeviation

protected double[] getTheoreticalStandardDeviation()

Get the theoretical standard deviation.

The theoretical standard deviation is a theoretical value used for normalizing the residuals. It acts as a weighting factor to mix appropriately measurements with different units and different accuracy. The value has the same dimension as the measurement itself (i.e. when a residual is divided by this value, it becomes dimensionless).

Returns:

expected standard deviation

See Also:

getBaseWeight()

getBaseWeight

protected double[] getBaseWeight()

Get the base weight associated with the measurement

The base weight is used on residuals already normalized thanks to getTheoreticalStandardDeviation() to increase or decrease relative effect of some measurements with respect to other measurements. It is a dimensionless value, typically between 0 and 1 (but it can really have any non-negative value).

Returns:

base weight

See Also:

getTheoreticalStandardDeviation(), EstimatedMeasurement.getCurrentWeight()

getSatellites

protected ObservableSatellite[] getSatellites()

Get the satellites related to this measurement.

Returns:

satellites related to this measurement