DSSTJ2SquaredClosedFormContext (OREKIT 12.1-SNAPSHOT API)

java.lang.Object
- org.orekit.propagation.semianalytical.dsst.forces.ForceModelContext
- - org.orekit.propagation.semianalytical.dsst.forces.DSSTJ2SquaredClosedFormContext

```
public class DSSTJ2SquaredClosedFormContext
extends ForceModelContext
```
This class is a container for the common parameters used in DSSTJ2SquaredClosedForm.
It performs parameters initialization at each integration step for the second-order J2-squared contribution to the central body gravitational perturbation.

Since:

12.0

Author:

Bryan Cazabonne

Constructor Summary

Constructors
Constructor	Description
`DSSTJ2SquaredClosedFormContext(AuxiliaryElements auxiliaryElements, UnnormalizedSphericalHarmonicsProvider provider)`	Simple constructor.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`double`	`getA4()`	Get the semi major axis to the power 4.
`double`	`getAlpha4()`	Get the equatorial radius of the central body to the power 4.
`double`	`getC()`	Get the cosine of the inclination.
`double`	`getEta()`	Get the eta value.
`double`	`getS2()`	Get the sine of the inclination to the power 2.

Methods inherited from class org.orekit.propagation.semianalytical.dsst.forces.ForceModelContext
getAuxiliaryElements

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

- Constructor Detail
  - DSSTJ2SquaredClosedFormContext
```
public DSSTJ2SquaredClosedFormContext(AuxiliaryElements auxiliaryElements,
                                      UnnormalizedSphericalHarmonicsProvider provider)
```
    Simple constructor.
    
    Parameters:
    
    auxiliaryElements - auxiliary elements related to the current orbit
    
    provider - provider for spherical harmonics
- Method Detail
  - getAlpha4
```
public double getAlpha4()
```
    Get the equatorial radius of the central body to the power 4.
    
    Returns:
    
    the equatorial radius of the central body to the power 4
  - getA4
```
public double getA4()
```
    Get the semi major axis to the power 4.
    
    Returns:
    
    the semi major axis to the power 4
  - getEta
```
public double getEta()
```
    Get the eta value.
    
    Returns:
    
    sqrt(1 - e * e)
  - getC
```
public double getC()
```
    Get the cosine of the inclination.
    
    Returns:
    
    the cosine of the inclination
  - getS2
```
public double getS2()
```
    Get the sine of the inclination to the power 2.
    
    Returns:
    
    the sine of the inclination to the power 2