org.orekit.propagation

Class AbstractMatricesHarvester

java.lang.Object

org.orekit.propagation.AbstractMatricesHarvester

All Implemented Interfaces:

MatricesHarvester

Direct Known Subclasses:

AbstractAnalyticalMatricesHarvester, DSSTHarvester

public abstract class AbstractMatricesHarvester
extends Object
implements MatricesHarvester

Base harvester between two-dimensional Jacobian matrices and one-dimensional additional state arrays.

Since:

11.1

Author:

Luc Maisonobe

Field Summary

Fields

Modifier and Type	Field and Description
static int	STATE_DIMENSION State dimension, fixed to 6.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	AbstractMatricesHarvester(String stmName, RealMatrix initialStm, DoubleArrayDictionary initialJacobianColumns) Simple constructor.

Method Summary

Modifier and Type	Method and Description
abstract void	freezeColumnsNames() Freeze the names of the Jacobian columns.
protected double[][]	getConversionJacobian(SpacecraftState state) Get the conversion Jacobian between state parameters and parameters used for derivatives.
double[]	getInitialJacobianColumn(String columnName) Get the initial column of Jacobian matrix with respect to named parameter.
RealMatrix	getInitialStateTransitionMatrix() Get the initial State Transition Matrix.
RealMatrix	getParametersJacobian(SpacecraftState state) Get the Jacobian with respect to propagation parameters.
RealMatrix	getStateTransitionMatrix(SpacecraftState state) Extract state transition matrix from state.
String	getStmName() Get the State Transition Matrix state name.
void	setReferenceState(SpacecraftState reference) Set up reference state.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.orekit.propagation.MatricesHarvester

getJacobiansColumnsNames

Field Detail

STATE_DIMENSION

public static final int STATE_DIMENSION

State dimension, fixed to 6.

See Also:

Constant Field Values

Constructor Detail

AbstractMatricesHarvester

protected AbstractMatricesHarvester(String stmName,
                                    RealMatrix initialStm,
                                    DoubleArrayDictionary initialJacobianColumns)

Simple constructor.

The arguments for initial matrices must be compatible with the orbit type and position angle that will be used by propagator

Parameters:

stmName - State Transition Matrix state name

initialStm - initial State Transition Matrix ∂Y/∂Y₀, if null (which is the most frequent case), assumed to be 6x6 identity

initialJacobianColumns - initial columns of the Jacobians matrix with respect to parameters, if null or if some selected parameters are missing from the dictionary, the corresponding initial column is assumed to be 0

Method Detail

getStmName

public String getStmName()

Get the State Transition Matrix state name.

Returns:

State Transition Matrix state name

getInitialStateTransitionMatrix

public RealMatrix getInitialStateTransitionMatrix()

Get the initial State Transition Matrix.

Returns:

initial State Transition Matrix

getInitialJacobianColumn

public double[] getInitialJacobianColumn(String columnName)

Get the initial column of Jacobian matrix with respect to named parameter.

Parameters:

columnName - name of the column

Returns:

initial column of the Jacobian matrix

getConversionJacobian

protected double[][] getConversionJacobian(SpacecraftState state)

Get the conversion Jacobian between state parameters and parameters used for derivatives.

The base implementation returns identity, which is suitable for DSST and TLE propagators, as state parameters and parameters used for derivatives are the same.

For Numerical propagator, parameters used for derivatives are Cartesian and they can be different from state parameters because the numerical propagator can accept different type of orbits, so the method is overridden in derived classes.

Parameters:

state - spacecraft state

Returns:

conversion Jacobian

setReferenceState

public void setReferenceState(SpacecraftState reference)

Set up reference state.

This method is called whenever the global propagation reference state changes. This corresponds to the start of propagation in batch least squares orbit determination or at prediction step for each measurement in Kalman filtering. Its goal is to allow the harvester to compute some internal data. Analytical models like TLE use it to compute analytical derivatives, semi-analytical models like DSST use it to compute short periodic terms, numerical models do not use it at all.

Specified by:

setReferenceState in interface MatricesHarvester

Parameters:

reference - reference state to set

getStateTransitionMatrix

public RealMatrix getStateTransitionMatrix(SpacecraftState state)

Extract state transition matrix from state.

Specified by:

getStateTransitionMatrix in interface MatricesHarvester

Parameters:

state - spacecraft state

Returns:

state transition matrix, with semantics consistent with propagation, or null if no state transition matrix is available orbit type.

getParametersJacobian

public RealMatrix getParametersJacobian(SpacecraftState state)

Get the Jacobian with respect to propagation parameters.

Specified by:

getParametersJacobian in interface MatricesHarvester

Parameters:

state - spacecraft state

Returns:

Jacobian with respect to propagation parameters, or null if there are no parameters

freezeColumnsNames

public abstract void freezeColumnsNames()

Freeze the names of the Jacobian columns.

This method is called when propagation starts, i.e. when configuration is completed