java.lang.Object
- org.orekit.propagation.StateCovarianceMatrixProvider

All Implemented Interfaces:

AdditionalStateProvider
```
public class StateCovarianceMatrixProvider
extends Object
implements AdditionalStateProvider
```
Additional state provider for state covariance matrix.
This additional state provider allows computing a propagated covariance matrix based on a user defined input state covariance matrix. The computation of the propagated covariance matrix uses the State Transition Matrix between the propagated spacecraft state and the initial state. As a result, the user must define the name of the provider for the State Transition Matrix.
As the State Transition Matrix and the input state covariance matrix can be expressed in different orbit types, the user must specify both orbit types when building the covariance provider. In addition, the position angle used in both matrices must also be specified.
In order to add this additional state provider to an orbit propagator, user must use the Propagator.addAdditionalStateProvider(AdditionalStateProvider) method.
For a given propagated spacecraft state, the propagated state covariance matrix is accessible through the method getStateCovariance(SpacecraftState)

Since:

11.3

Author:

Bryan Cazabonne, Vincent Cucchietti

Constructor Summary

Constructors
Constructor	Description
`StateCovarianceMatrixProvider(String additionalName, String stmName, MatricesHarvester harvester, StateCovariance covInit)`	Constructor.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`double[]`	`getAdditionalState(SpacecraftState state)`	Get the additional state.
`OrbitType`	`getCovarianceOrbitType()`	Get the orbit type in which the covariance matrix is expressed.
`String`	`getName()`	Get the name of the additional state.
`StateCovariance`	`getStateCovariance(SpacecraftState state)`	Get the state covariance in the same frame/local orbital frame, orbit type and position angle as the initial covariance.
`StateCovariance`	`getStateCovariance(SpacecraftState state, Frame frame)`	Get the state covariance expressed in a given frame.
`StateCovariance`	`getStateCovariance(SpacecraftState state, OrbitType orbitType, PositionAngleType angleType)`	Get the state covariance expressed in a given orbit type.
`void`	`init(SpacecraftState initialState, AbsoluteDate target)`	Initialize the additional state provider at the start of propagation.
`boolean`	`yields(SpacecraftState state)`	Check if this provider should yield so another provider has an opportunity to add missing parts.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - StateCovarianceMatrixProvider
```
public StateCovarianceMatrixProvider(String additionalName,
                                     String stmName,
                                     MatricesHarvester harvester,
                                     StateCovariance covInit)
```
    Constructor.
    
    Parameters:
    
    additionalName - name of the additional state
    
    stmName - name of the state for State Transition Matrix
    
    harvester - matrix harvester as returned by propagator.setupMatricesComputation(stmName, null, null)
    
    covInit - initial state covariance
- Method Detail
  - getName
```
public String getName()
```
    Get the name of the additional state.
    
    Specified by:
    
    getName in interface AdditionalStateProvider
    
    Returns:
    
    name of the additional state (names containing "orekit" with any case are reserved for the library internal use)
  - init
```
public void init(SpacecraftState initialState,
                 AbsoluteDate target)
```
    Initialize the additional state provider at the start of propagation.
    
    Specified by:
    
    init in interface AdditionalStateProvider
    
    Parameters:
    
    initialState - initial state information at the start of propagation
    
    target - date of propagation
  - yields
```
public boolean yields(SpacecraftState state)
```
    Check if this provider should yield so another provider has an opportunity to add missing parts.
    Decision to yield is often based on an additional state being already available in the provided state (but it could theoretically also depend on an additional state derivative being already available, or any other criterion). If for example a provider needs the state transition matrix, it could implement this method as:
    
    public boolean yields(final SpacecraftState state) { return !state.getAdditionalStates().containsKey("STM"); }
    
    The default implementation returns false, meaning that state data can be generated immediately.
    
    The covariance matrix can be computed only if the State Transition Matrix state is available.
    Specified by:
    
    yields in interface AdditionalStateProvider
    
    Parameters:
    
    state - state to handle
    
    Returns:
    
    true if this provider should yield so another provider has an opportunity to add missing parts as the state is incrementally built up
  - getAdditionalState
```
public double[] getAdditionalState(SpacecraftState state)
```
    Get the additional state.
    
    Specified by:
    
    getAdditionalState in interface AdditionalStateProvider
    
    Parameters:
    
    state - spacecraft state to which additional state should correspond
    
    Returns:
    
    additional state corresponding to spacecraft state
  - getCovarianceOrbitType
```
public OrbitType getCovarianceOrbitType()
```
    Get the orbit type in which the covariance matrix is expressed.
    
    Returns:
    
    the orbit type
  - getStateCovariance
```
public StateCovariance getStateCovariance(SpacecraftState state)
```
    Get the state covariance in the same frame/local orbital frame, orbit type and position angle as the initial covariance.
    
    Parameters:
    
    state - spacecraft state to which the covariance matrix should correspond
    
    Returns:
    
    the state covariance
    
    See Also:
    
    getStateCovariance(SpacecraftState, Frame), getStateCovariance(SpacecraftState, OrbitType, PositionAngleType)
  - getStateCovariance
```
public StateCovariance getStateCovariance(SpacecraftState state,
                                          Frame frame)
```
    Get the state covariance expressed in a given frame.
    The output covariance matrix is expressed in the same orbit type as getCovarianceOrbitType().
    
    Parameters:
    
    state - spacecraft state to which the covariance matrix should correspond
    
    frame - output frame for which the output covariance matrix must be expressed (must be inertial)
    
    Returns:
    
    the state covariance expressed in frame
    
    See Also:
    
    getStateCovariance(SpacecraftState), getStateCovariance(SpacecraftState, OrbitType, PositionAngleType)
  - getStateCovariance
```
public StateCovariance getStateCovariance(SpacecraftState state,
                                          OrbitType orbitType,
                                          PositionAngleType angleType)
```
    Get the state covariance expressed in a given orbit type.
    
    Parameters:
    
    state - spacecraft state to which the covariance matrix should correspond
    
    orbitType - output orbit type
    
    angleType - output position angle (not used if orbitType equals CARTESIAN)
    
    Returns:
    
    the state covariance in orbitType and angleType
    
    See Also:
    
    getStateCovariance(SpacecraftState), getStateCovariance(SpacecraftState, Frame)

Class StateCovarianceMatrixProvider

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

StateCovarianceMatrixProvider

Method Detail

getName

init

yields

getAdditionalState

getCovarianceOrbitType

getStateCovariance

getStateCovariance

getStateCovariance